ArticlePDF Available

A Formative Assessment of Geologic Time for High School Earth Science Students

Authors:

Abstract

Earth science courses typically include the concept of geological time. Traditional approaches to teaching geologic time have turned to constructivist methodologies in an attempt to increase student understanding, but these lessons often result in students determining the scale of geologic time instead of gaining an increased understanding of the geologic time scale. Here students create a geologic time scale based on an older adult's life complete with relative and absolute dates for the events m their lives. Students write a reflective paper about the process of constructing the time scale and compare their scales to the geologic time scale. The project is used as a formative assessment which serves to inform instruction, rather than assess students on the project. To that end, students submit project drafts for review and are given immediate feedback regarding improvements to the project. Through this process the teacher gains valuable insight into the direction instruction should take based on common misunderstandings or questions that arise during conversations with students.
A Formative Assessment
of
Geologic Time for High
School
Earth
Science
Students
Ron Hermann
Bradford Lewis
Morgan State University, Baltimore, MD 21251, rhermann@bpcl.net
Morgan State University, Baltimore,
MD
21251, blewis@moac.morgan.edu
ABSTRACT
Earth
science courses typically include the concept of
geological time. Traditional approaches to teaching
geologic time
have
turned
to constructivist
methodologies
in
an
attempt
to increase
student
understanding,
but
these lessons often result
in
students
determining
the scale of geologic time instead of gaining
an
increasea
understanding
of the geologic time scale.
Here
students
create a geofogic time scale
based
on
an
older
adult's
life com:plete
with
relative
and
absolute
dates for the events m their lives.
Students
write a
reflective
paper
about
the process of constructing
the
time scale
and
compare
their scales to the geologic time
scale. The project is
used
as a formative assessment
which
serves to inform instruction, rather
than
assess
students
on
the
project. To
that
end,
students
submit
project drafts for
review
and
are given
immediate
feedback
regarding
improvements
to the project.
Through
this process the teacher gains valuable insight
into tfie direction instruction
snould
take
based
on
common
misunderstandings
or
questions that arise
during
conversations
with
students.
INTRODUCTION
There are multiple
ways
in
which
teachers traditionally
assess
students'
conceptions of geologic time.
One
traditional
method
provides
students
with
a list of
geologic events
which
students
put
in
the correct
sequential order, scaled to the length of
adding
machine
tape. This
method
results
in
an
assessment
of
students'
understanding
of
the
mathematical process
needed
for
comprehending
scale
rather
than
assessing
an
understanding
of geologic time. Science educators
have
strived
to develop
more
innovative lessons
with
a
constructivist methodology (Hemler & Repine, 2002) so
that
students
develop
a
deep
understanding
and
appreciation for the concept of geologic time. Here,
we
move
past
traditional assessment practices
and
develop
a formative assessment of
students'
understanding
of the
construction of the geologic time scale
and
how
it is
interpreted.
Through
this
approach
students
are
challenged to conceptualize
the
geologic time scale by
comparing
it
to a
student-produced
time scale for
an
older
adult's
life. This formative assessment allows the
teacher to alter instruction
based
on
students'
feedback
in
order
to maximize
student
understanding
of geologic
time.
GEOLOGY BACKGROUND
High
school
earth
science courses typically cover basic
geologic principles,
such
as the principle
that
the Earth is
approximately 4.6 billion years old. To account for such a
large
period
of time, geologists have
divided
the
4.6
billion years into smaller segments of time based
on
major events
in
Earth's history. This concept,
known
as
"geologic time", is universally accepted by scientists
and
is used in the description
and
analysis of events of
Earth's past.
Geologic time is
measured
in
four units: eons, eras,
periods,
and
epochs. These units are
grouped
in
a
hierarchy; however, the length of absolute geologic time
that
each
unit
represents is different. Eons are the largest
unit
of time,
and
are
divided
into eras. Eras,
in
turn, are
divided
into periods,
and
periods
are
divided
into
epochs (the smallest
unit
of geologic time). The actual
duration
of time varies for each
unit
of geologic time. For
example,
an
era
may
last several tens
of
millions years
or
several
hundreds
of million of years. The
duration
of
an
era
depends
upon
the significant geologic events
and
chan~es
in
fossil
type
or
abundance
that
occurred
during
that
time. The Mesozoic Era lasted from
245
million years
ago
until65
million years ago, a total of 180 million years.
These times
mark
two
significant events: the emergence
of dinosaurs
245
million years ago
and
the extinction of
dinosaurs
65
million years ago.
Geologists have constructed
two
ways
to determine
geologic time: absolute
dating
and
relative dating.
Absolute
dating
is the process
of
determining
the actual
age of
an
object,
perhaps
a fossil
or
bone,
through
radiometric
dating
techniques. Radiometric
dating
is
possible
due
to radioactive decay, a process
in
which
the
parent
atoms change into
daughter
atoms
by
loosing
or
gaining subatomic particles (Conte, Thompson, &
Moses, 1994). For
exam~le
half of the atoms of tfi.eparent
element
potassium
(K
4 ) convert into
Argon
(Af'll')
over
the course of 1,300,000,000 years. Since this decay
happens
at
a constant rate,
one
can
surmise
the age of
an
object by determining the ratio of the
parent
element
(potassium) to the
daughter
element (argon).
Relative
dating
is the process of
determining
whether one object is
older
or
younger
than
another
object. This process is
used
when
the absolute age is
not
known. Relative
dating
techniques are based
on
the
law
of uniformitarianism,
which
maintains
that
the geologic
events
and
processes
that
are
observable
today
must
be
the
same
geologic events
that
happened
in
the past.
Therefore,
by
assuming
similarity
between
current
and
past
geological processes, geologists can infer the
sequence
of
past
events.
EDUCATIONAL RESEARCH OF GEOLOGIC
TIME
The
phrase
"geologic time" often is extended
beyond
the
geologic time scale to refer to the comprehension of
geologic principles
that
are based
on
the geologic time
scale. This
fundamental
understanding
of geologic time
is a prerequisite for a
deeper
understanding
of geologic
principles such as original horizontality, superposition,
and
others associated
with
interpreting rock layers
and
embedded
fossils. Therefore, this assessment becomes
an
important
tool that can help teachers determine
whether
students
are capable of
understanding
more
challenging
Hermann
and
Lewis - A Formative
Assessment
of
Geologic
Time
231
Laura's
Time
Line
Eras Periods Relative Absolute
Dates
Dates
Infancy Infancy Birth January
27,
1953
Toddler Moved to MD
I
Moved to
Childhood Elementary
Lon~
Bar
Har
or
School Moved back
toIL
Pre-teen Met best
friend Eric
Young
Adult
Started High
School
Teen
Graduated
fromH.S
June6,
1971
··············-----
······----
····-·-··-·---··-··-····--
······----·--·--
...........
-------------------
Father Passed April
9,
1973
Away
Tough Times
Acehted
Jesus rist as
Savior
Started
Criminal
_].!:!~!!~':!.
Car!,!_E:!!
__
------··
-·······-··-
Adulthood
Career Started Dating
Joyce
Started
Worki,for
Harfor Co.
--------------------------
···-·-
~h~!iff'
s
.Q~
f--···-····-
-----------·-·
Married Joyce April18, 1978
Married
f----·-.£..··--
······-·····-·····-----··
Moved into
first house
Birth of Krista April19, 1983
W.
Moved to
Family Current
House
Family Birth of Laura May16, 1988
and
Leslie
W.
Retired from
Retired
Harford
Co. Oct. 31,2002
Sheriff's
Office
Table
1.
Laura's
time
line
of
her
father's
life.
problems
regarding
geologic time. Dodick
and
Orion
(2003)
have
suggested that it is possible to start teaching
the logical principles
used
in geology to reconstruct
geological structures somewhere between grades 7
and
8.
Their research suggests, however, that students in
higher grades fair significantly better
on
assessment
measures
regarding
geologic time. The assessment
outlined here is intended for
high
school students
who
should
be cognitively capable of
understanding
geologic
time.
In dealing
with
such
an
enormous time scale,
students
and
teachers often struggle
with
the sequence of
events
and
an estimation of the time between events. A
common
problem
is
that
events that
happened
at
two
different periods of Earth's history are either perceived
to
happen
at
the
same
time or
with
less time in between
the events. Trend (2001)
noted
that
primary school
in-service teachers
tend
to place events into three
categories: extremely ancient, moderately ancient,
and
less ancient. Teachers,
and
students, place
past
geologic
events into these categories based
on
prior knowledge of
geologic time or existing schemata
with
connections to
the prior conception of time. This suggests
that
difficulty
exists, for both teacher
and
student,
when
attempting to
assign
an
absolute date to
an
event. Dodick
and
Orion
(2003)
noted
that a large portion of their sample
population of
middle
and
high
school
students
did
not
understand
absolute time measurement; hence the
students partitioned strata into equal portions of time, as
if they were units on a ruler. Their findings suggest
that
students view the units of geologic time as equal units of
time instead of varied
amounts
of time based
on
the
occurrence of significant geological events. Furthermore,
students
with
a weak
understanding
of Earth's history
may
have
an
alternative perception of relative time
and
the
amount
of time between geologic events
may
not
be
fully recognized. Events that occur
hundreds
of millions
of years
apart
may be perceived to
happen
with
the
same
passing of time as events that occur only millions of years
apart. A complete
understanding
of geologic time
can
be
identified
by
an
understanding
of,
not
only the dates of
occurrence
or
relative sequence of particular events,
but
also the time
span
between events.
THEORETICAL UNDERPINNINGS
To facilitate
an
understanding
of the scientific principles
underlying
l?ieologic
time, this assessment occurs
within
the instructional period, as
opposed
to an end-of-unit
evaluation. Shepard (2000) refers to this as dynamic,
on-going assessment that allows teachers to find
out
what
students are able to
do
independently
and
what
can
be done
with
adult
guidance -
an
integral
part
of
Vygotsky' s idea of the zone of proximal development.
Vygotsky's (1978) concept of zone of proximal
development (ZPD) bridges the
gap
between
what
a
student
knows
and
what
can be known. This assessment
can also be categorized as a formative assessment. The
purpose
of a formative assessment is to determine
what
adjustments
should
be
made
to instruction (Oosterhof,
1999). This approach allows instructors to interact
with
students
and
provide assistance as
part
of the
assessment.
The potential to provide feedback
students
can use
to self-assess their
understanding
is greatly increased
when
assessment is
moved
to the middle of instruction.
The best feedback, according to Wiggins (1998), is
"highly specific, directly revealing or highly descriptive
of
what
actually resulted, clear to the performer,
and
available or offered in terms of specific targets
and
standards" (p. 46). Feedback is
more
effective
when
students have
an
opportunity
to change their thinking
and
improve
understandins.
Therefore, feedback
may
be
ineffective
at
the end-of-umt evaluation if
students
don't
see
benefit
in
improving understanding after instruction.
Likewise, teachers
may
also receive feedback from
students. However, this
opportunity
may
be lost
at
the
end
of the instructional
umt
as the time
may
have passed
to change instructional approaches.
DESCRIPTION OF THE ASSESSMENT
This long-term, formative assessment requires
students
to synthesize information
and
solve a novel problem,
over a three-week time frame. Students are asked to
232
Journal
of
Geoscience
Education,
v. 52, n. 3, May, 2004, p. 231-235
Sam's
Time
Line
Eras Periods Relative
Time
Absolute
Time
Birth
May3,
1929
Care-free time Childhood Two room
schoolhouse
Y\'WI!J3egins
__
__Dec.
7,
!?•g
__
Young
Adult
Met
Husband
in
High
World War
II
School
Adult
First Job
1----··-
·------··----·-
WWIIEnded
··--------·-·········
Married
April2,
1949
Wife First
Ca~~~941
Chev
Parent
First Child Oct. 22,1949
Born
Bought House Apri128, 1962
Family Home-owner Last Child
Born Dec.
26,
1967
First Jan.16,1968
Grand-child
Grand-parent Father Elected
County
Commissioner
Retired July 8,1988
Relaxing Time Retiree Began Line
Dancing
Table
2.
Sam's
time
line
of
her grandmother's life.
interview a
grandparent
or
older
community
member
and
gather
data
to
make
a geologic timescale of
that
person's
life.
Students
then
select 15 events of the
person's
life
and
arrange
them
sequentially from the
most
recent
event
to the oldest event. These events
represent
relative
dates
of the
person's
life. These are
events
in
which
the exact
date
of
the
event
is
unknown,
but
the
event
is memorable.
Students
also identify 8 exact
dates for events
that
represent absolute dates. These are
significant events
in
the
person's
life, for
which
the exact
date
on
which
the
event
occurred is known. Next,
students
develop segments of the older
adult's
life
that
represent
si~iflcant
stages. These stages are
separated
into
two
umts
of time
representin~
eras
and
periods of
geologic time. Large segments of time
are
referred to as
eras
and
the smaller units of time are referred to as
periods.
Students
negotiate
with
the interviewed
person
to decide
how
his
or
her
life can be
divided
into
significant segments representing eras
and
yeriods.
These segments of time are basecf
on
the list o events
already placed
on
the time scale. Each
student
then
constructs a time scale
and
writes a reflection
paper
on
the process.
Two
examples of time scales are
shown
in
Tabie 1
and
Table
2.
The instructor meets
with
students
during
construction of the time scale to offer feedback.
Students
make
adjustments to the time scale as
needed
based
on
feedback
and
self-assessment. The instructor can adjust
whole
class,
group,
or
individual
instruction
based
on
common
misunderstandings
presented
in
students'
work. Adjusting instruction permits the instructor to
address
misunderstandings
that
may
go unnoticed in a
summative
evaluation
at
tne
end
of
an
instructional unit.
Once the instructor has
met
with
students
and
everyone agrees
that
the time scale meets the
requirements (see section
on
scoring below)
students
begin writing a reflection paper. The
paper
requires each
student
to reflect
on
the process of timeline construction
and
compare
his/her
timeline to the geologic time line.
Reflection
papers
should
include the following:
1.
2.
3.
4.
5.
a statement of
how
this timeline is similar to the
geologic time line;
a statement of
how
this timeline is different
than
the
geologic time line;
a description of the difference between absolute
and
relative dating;
an
explanation for the
manner
in
which
eras
and
periods were decided;
and
a comparison of
how
the segments of the geologic
timeline are similar to the
older
adult's
time line.
Initial drafts of the reflection
paper
are
shared
with
the instructor for review, feedback is given
on
the
paper
through
dialogue
with
individual
students
and
through
written
comments. For
promoting
thought
and
reflection; the
most
effective
type
of feedback is the
use
of
questions
aimed
at
eliciting
more
detailed responses
from students. Typical questions were,
"What
are the
similarities
between
the older
adult's
timeline
and
the
geologic timeline
with
respect to
how
the
duration
of
time segments
were
developed?"
and
"By looking
at
the
older
adult's
timeline
you
can infer
that
some events
occur between events hsted. Do
you
think the geologic
timeline allows scientists to make similar inferences?"
Grammatical errors
and
errors
in
sentence structure are
also identified
so
that
students
may
correct these errors.
Common
themes
that
represent
misunderstandings
may
be identified
during
this process. These
may
be
addressed
through
re-teachmg
or
lessons
may
be
developed to further clarify a topic
that
was
problematic
for students. For example, instruction
regarding
radioactive
dating
might
occur
prior
to this assessment.
If
it
becomes clear that
students
are
not
connecting the
process of radioactive
dating
to the absolute age
of
an
object, a
new
lesson
could
be
presented
in
wnich
the
connection
between
absolute age
and
radioactive
dating
would
be
made
more
explicit.
SCORING
Students are given the
parameters
of the assignment
and
the scoring rubric (Table
3)
simultaneously. The scoring
rubric states the performance objectives
and
provides
descriptions of performance
rating
categories. According
to Airasian (1997) the scale of a rubric
should
have
an
optimal
amount
of
between
three
and
five rating
categories. The scoring rubric contains descriptive
summaries for each of the different categories of
student
performance. These categories of performance
were
labeled
with
descriptions
such
as "excellent," "good,"
"fair,"
and
"poor." This analytical rubric divides the
product
into several dimensions so that each can be
judged
separately
providing
specific feedback
about
each dimension (Arter & McTighe, 2001). Before
the
project commences,
students
are
given a
copy
of
the
rubric so
that
a comparison can be
made
between
the
students'
products
and
the idealized performance rating
categories from the rubric (Table
3).
Students
and
instructor are able to compare the
students'
project to the
Hermann
and
Lewis - A Formative
Assessment
of
Geologic
Time
233
Geologic
Time
Scale
Dimension
r----
!l!~~~_!!.t
______
___________
<:;..Q.od
_
____________
]'air·····---------
_______
Poor
______
----····-------··-·-·-----
Includes
all15
relative Includes between 13-14 Includes between 11-12 Includes fewer
than
10
Number
of Events dates
and
8 absolute relative dates or between relative dates or between relative dates
or
fewer
r---·····---------·····---
1--··----······---dat~,_
____________
6-7
absolute dates. _ _
_±!?__~l?_solut~.:Iates,
__
____
than_~
__
absoll!t~
date_~'---
-----··-·-·-···--------·-··
Understanding of Events are
clearlt
Partial confusion of Seemingly little Extreme!& difficult to
relative
or
absolute or a relative
and
absolute difference between
why
Relative Dates
and
reason which is evident dates evident
in
the time events were selected to discern a solute from
Absolute Dates in the time scale. scales structure. be relative or absolute. relative events.
Selection of eras
and
Selection of eras
and
Selection of eras
and
Selection of eras and
Selection of Eras
and
periods
is
logical
and
periods
is
periods is uncertain
and
periods
is
seemingly
Periods understandable
but
needs further
random
and
not
requires
no
speculation. raises questions. clarification. comprehensible.
Time scale
is
neatly Time scale is neatly Time scale
is
disorderly
produced
as Time scale is not neatly
produced
as word-processed table
or
produced
or
is
not
of the
in
groduction
and size
word-processed table or
Presentation of Geologic
d~awin~
of appropriate
drawing
of appropriate appropriate size
or
an
arrangement is
not
TimeScale size
ana
arrangement. arranfi7ment. Four to six appropriate. Greater
than
sJze
an
arrangement. One to three spelling, spe mg,
grammar
or
seven spelling,
reammar
Spelling,
grammar
and
mechanics are correct. grammar
or
mechanical mecharucal errors.
or
mechanica errors.
errors .
--------·--·····--
........
_
..
______
..
__
......
___
...
_
..
____
..
____
....
_.Kefle<;.tiQ!!_!'aper
-·-·---
..
·---------------
....
,--
.............. , ___ ,
________
A complete
and
Numerous similarities Few similarities
and
Similarities
and
Similarities
and
thorough comparison
and
differences are listed differences are listed
and
differences are onp;
Differences to Geologic
made
between the
but
they lack they lack thoroughness described
in
terms o the
Time Line constructed timeline
and
structure of the time
the geologic timeline. thoroughness
and
detail.
and
detail. lines.
Description of the A com£lete
and
An
accurate description A partial description is
Difference Between
thorough
escription is is given
and
reference
is
given
and
little reference The description is
vague
Absolute
and
Relative given
and
analogies are
made
to the constructed is
made
to the
and
the timeline
is
not
Dating
made
to the constructed timeline. constructed timeline. referenced.
timeline.
Explanation of the A detailed, logical A detailed
ex~anation
is
An
ex~anation
is
tven,
A vague explanation is
Manner
in
Which Eras explanation is given for given,
but
lac s a loJ.ical
but
lac s detail
an
logic given with no logical
selection of eras
and
and
Periods were Chosen periods. selection metho . of selection method. selection method.
Comparison of the A detailed
and
complete The comparison lacks A superficial Little
understanding
of
comparison of the detail
and
completeness,
why
the segments of
Construction of the reasons the segments of
but
does comyare the understanding of
whfa
each timeline
appear
as
Geolo~ic
and
Older
geolo~c
time are similar segments o time each timeline has simi
ar
they do
tven
the events
Adult
s Time Line to t e older
adult's
between the two construction of segments.
timeline. timelines. I
needed
or construction.
Spelling,
grammar
and
One to three spelling, Four to six
spellin~,
Greater
than
seven
Presentation of mechanics are correct. grammar or mechanical
grammar
or
mecharucal spelling,
grammar
or
Reflection
Paper
Writing is well organized errors. Writing is errors. Writing lacks mechamcal errors.
-
----------------
--------···--·-- ------
----------------
---------------------·····
---
_organized.
______
......
,_~i!P!l_g_Q!g<_l:':l:!zati':':J!l:
_
-~rit~I}g}s
di_~<,>rgani~eE_:_
Table
3.
Scoring
rubric
used
by
students
and
teacher
for
assessing
the
geologic
time
scale
project.
rubric to assess the strengths
and
weaknesses of the
project, thereby becoming better
at
self-assessment.
Students begin to realize
what
they have learned
and
what
they need more help with, thus actively
participating in their education.
Depending
upon
the
outcome of self-assessment
and
negotiations
with
the
instructor
students
make changes to the project.
Likewise,
if
the instructor realizes that students, as a
group, are
weak
in a given area, lessons are altered to
address
these issues
and
suggest considerations that
students
may
have
overlooked or were
not
cognizant of
while developing the project.
FIELD TEST OF THE PROJECT
A field test
was
conducted by
Hermann
with
140
ninth-grade
earth
science
students
in
a
suburban
high
school
in
the mid-Atlantic region. Initially, students were
apprehensive
about
submitting drafts for review.
Students were largely unfamiliar
with
formative
assessment
and
felt they might be assessed
on
rough
drafts, or that asking for help
meant
they were
not
at
the
same cognitive level as their peers. Therefore,
the
instructor
should
discuss the
purpose
of formative
assessment
with
the class.
The time lines of
two
students, Laura (Table
1)
and
Sam (Table
2),
provide examples of completed projects.
Both time lines begin
with
the birth of the older adult,
whereas the geologic time line begins
with
present
day
and
extends
bacl<
to the formation of earth. Most
students constructed their time lines
in
this
manner
as
everyday thinking probably precludes students from
viewing life
spans
as directional
towards
present
day.
Laura's time fine is indicative of a
common
tendency
among
students to label some eras
and
periods the same,
for example both era
and
period are labeled "family".
Perhaps tbis is
due
to the structure of the geologic time
line,
in
which some periods are
not
divided into epochs,
for example the cretaceous period. Laura's time line
provides more detailed information in the relative
date's
column, while Sam's time line has a more consistent
overall structure
where
eras are divided into periods
based
upon
major events. Similar to the geologic time
234
Journal
of
Geoscience
Education,
v. 52, n. 3,
May,
2004, p. 231-235
line,
both
examples contain events
that
mark
the
beginning
and
end
of eras
and
periods. For example,
Sam's
grandmother
was
affected by the beginning
and
ending
of
World
War
II, so
that
era
of
her
liie is labeled
"World
War
II".
Other
events
are
vague,
such
as Laura's
choice of labeling
an
era as
"young
adult"
which
lacks a
major
be~inning
and
ending
event. These
two
examples
also depict a
higher
frequency of events
in
the older
adult's
life
with
increasing proximity to
present
day,
possibly
due
to memories
that
are
more
readily recalled.
More important, is the observation
that
both
Laura
and
Sam
gained a better sense of
how
and
why
segments of
geologic time
are
divided
into subsections.
The reflection
paper
provided
greater insight into
understanding
of geologic time line construction. Within
the reflection
paper
some
students
needed
to
be
prompted
to elaborate
on
similarities
and
differences
between
the constructed time line
and
the geologic time
line.
Students
also
needed
to be asked to
expand
on
the
reason
why
the eras
and
periods were constructed as
they
were. Laura
provides
a fairly
common
example
when
she
said,
"The
manner
in
which the eras
and
periods
were
decided
was
that
first I
determined
the
periods
and
then
I picked the
era
that
would
best
describe
or
summarize
the periods. I determined the
periods
by
knowing
when
the events occurred." Laura's
statement
was
the
result
of a discussion
regarding
a
rough
draft
she
submitted
previously, in
which
she
did
not
explicitly state
that
the events governed the
establishment of eras
and
periods. This example
illustrates the benefits of a formative assessment,
where
the
instructor
can
determine if a
student
has
an
understanding
of a concept
and
did
not
communicate the
concept clearly
or
simply
had
not
fully developed the
concept. As a
summative
evaluation the instructor
would
subtract
grade
points,
not
knowing
if
the
student
understood
the concept and,
more
importantly, the
student
may
never
come to
understand
the concept.
During
the creation of reflection
papers
students
provided
input
that
shaped
the course of instruction. As
students
began
reflecting
on
the process of creating
the
older
adult's
timeline they raised questions
that
suggested
that
the instructor either
spent
too little class
time discussing
or
neglected to cover
with
adequate
scope. The formative assessment structure
provided
an
opportunity
for
students
to inform instruction
and
determine
what
concepts
should
be
more
thoroughly
discussed to enrich
student
understanding.
CONCLUSIONS
A dynamic, on-going assessment such as this allows for
immediate
and
useful feedback
that
students
can use to
improve
their
understanding
of the topic. Likewise,
teachers are
provided
with
valuable feedback
regarding
the degree to
which
instruction is effective
in
increasing
students'
knowledge
of a concept. While the intent is to
change instruction
based
on
students'
feedback, a
subsequent
increase
in
students'
understanding
develops from teacher feedback.
Only
by modifying
instruction based
on
the
input
of
students
can teachers
expect
students
to become better learners.
Through
an
ongoing dialogue
with
the teacher,
students
deve1op a
greater
understanding
of
not
only geologic time,
but
also
how
to develop procfucts,
through
use
of a rubric,
that
meet the expectations of the scientific community.
Students can
perform
to a greater level of excellence
when
the task is clearly defined, the instructions
are
precisely stated, the performance rating categories are
clearly defined within a scoring rubric,
and
the
assessment is on-going.
Based
on
this project, one factor
that
affects the
degree to
which
a formative assessment is effective is the
students'
prior
exposure to this assessment technique.
Students expressed a lack of familiarity
with
formative
assessments,
suggestin~
that
summative
evaluations
are
still the
norm
among
science educators. Clearly,
students
benefit from exposure to the formative assessment
process, as it
may
help
students
reach a higher degree of
understanding
through
increased teacher input. With
abstract conceptions such as geologic time, teachers
benefit from the increased cfialogue
with
students
afforded
during
formative assessment
and
have
the
opportunity
to modify instruction to maximize
student
understanding.
REFERENCES
Airasian,
P.
W., 1997, Classroom assessment,
3rd
ed,
McGraw-Hill.
Arter,
J.,
and
McTighe,
J.,
2001, Scoring rubrics
in
the
classroom: Using performance criteria for assessing
and
improving
student
performance,
Thousand
Oaks, California ,Corwin Press, Inc.
Conte,
D.
J.,
Thompson,
D.
J.,
and
Moses,
L.
L., 1994,
Earth science: A holistic approach,
Dubuque,
Iowa,
Wm.
C.
Brown Publishers.
Dodick,
J.
T.
and
Orion, N., 2003, Cognitive factors
affecting
student
understanding
of geologic Time,
Journal of Research
in
Science Teaching, v. 40, p.
415-442.
Hemler,
D.
& Repine, T., 2002, Reconstructing
the
geologic timeline:
Adding
a constructivist slant to a
classical activity, The Science Teacher, v. 69, p. 32-35.
Oosterhof, A., 1999, Developing
and
using
cfassroom
assessments,
2nd
ed,
New
Jersey, Prentice Hall.
Shepard,
L.
A., 2000, The role of assessment
in
a learning
culture, Educational Researcher,
v.
29, p. 4-14.
Trend, R., 2001, Deep time framework: A preliminary
study
of UK
primary
teachers' conceptions of
geological time
and
perception of geoscience,
journal
of Research
in
Science Teaching, v. 38, p.
191-221.
Vygotsky, L.S.,
1978,
Mind
and
society: The
development
of
higher
mental processes,
Cambndge,
Harvard
University Press.
Wiggins,
G.
P., 1998, Educative assessment: Designing
assessments to inform
and
improve
student
performance San Francisco, Jossey-Bass Inc.
Hermann and Lewis - A Formative Assessment of Geologic Time 235
... Different types of feedback are discussed, such as comment-only marking by teachers (Black & Harrison, 2001;Wiliam et al., 2004), oral feedback offered informally and responsively during classroom activities (Bell & Cowie, 2001), or computer-generated feedback that is tailored to specific errors (Thissen-Roe et al., 2004). Rubrics are used as a feedback tool, to direct student attention to specific dimensions of an assignment (Hermann & Lewis, 2004), or to guide feedback conversations that involve peers in discussion about learning (Hickey & Zuicker, 2005, p. 297). While these studies do not give indication of the relative merits of these different methods of feedback, positive consequences are generally seen. ...
... Even experienced teachers can be surprised by student's misunderstandings (Bell & Cowie, 2001;Thissen-Roe et al., 2004), and in learning formative strategies, teachers are better able to use assessment information (Bell & Cowie, 2001;Hand & Prain, 2002). Teachers in these studies draw on a variety of assessment sources to inform their teaching, from students' responses to oral questions (Bell & Cowie, 2001;Black & Harrison 2001), student interaction with computer simulations (Vendlinski & Stevens, 2002), discussion in group problem solving (Leat & Nichols, 2002), individual products (Hermann & Lewis, 2004), and portfolios (Barootchi & Keshavarz, 2002). The teachers in Bell and Cowie's (2001) study describe different types of action under the umbrella of formative assessment, from proactive and planned to reactive and spontaneous, and they list a host of ways in which assessment can support a range of teaching activities, from planning to reporting. ...
... The articles involve student formative assessment using portfolio assessments (Barootchi & Keshavarz, 2002;Clark et al., 2001;Nunes, 2004;Simon & Forgette-Giroux, 2000;Torres Pereira de Eca, 2005), or they focus more specifically on peer and student self-assessment (Black & Harrison, 2001;Davies et al., 2004;McDonald, 2002;McDonald & Boud, 2003;Noonan& Duncan, 2005). In some, peers support or mediate the learning and assessment process (Bell & Cowie, 2001;Cowie, 2005;Hickey & Zuicker, 2005;Kirkwood, 2000;Wiliam et al., 2004;Yung, 2001), and in others, student selfassessment plays a strong role in the learning and assessment activities (Brookhart, 2001;Hand & Prain, 2002;Hermann & Lewis, 2004). The importance of student involvement in assessment is also suggested in some of the texts that take a broader look at the context in which classroom assessment occurs (Dori, 2003;Hayward et al., 2004;Stokking et al., 2004). ...
Article
The purpose of this study was to examine whether comprehensive post formative assessments can accurately predict student academic achievement on AYP (Adequate Yearly Progress) indicators as measured by standardized criterion-referenced tests. The primary participant populations for this study were sixth, seventh, and eighth grade students enrolled in a middle school in north Georgia from 2004-2007. Over 2,900 student assessments were used to conduct the statistical research and variables such as gender, race, and socio-economic levels were not disaggregated in the data collection compilation. The data sources included the first quarter, second quarter, and third quarter post formative assessments which are administered every nine-week grading period in the school system. The findings indicated that various grade levels exhibited a higher predictability factor with certain quarterly assessments than others. Likewise, unit gains on post assessments demonstrated a statistically significant indicator for academic achievement on high stake standardized assessments.
... assignment (Hermann & Lewis, 2004), mysteries (Leat & Nichols, 2000), invention activities (Schwartz & Martin, 2004), and several computer-based tools (Thissen-Roe et al., 2004;Vendlinski & Stevens, 2002). Articles in the fourth group describe classroom assessment practices in which the formative function plays a significant role (Brookhart, 2001;Cowie, 2005;Doppelt, 2003;Hickey & Zuicker, 2005;Kirkwood, 2000;Stokking, van der Schaaf, Jaspers, Erkens, 2004). ...
... informally and responsively during classroom activities (Bell & Cowie, 2001), or computergenerated feedback that is tailored to specific errors (Thissen-Roe et al., 2004). Rubrics are used as a feedback tool, to direct student attention to specific dimensions of an assignment (Hermann & Lewis, 2004), or to guide "feedback conversations" that involve peers in discussion about learning (Hickey & Zuicker, 2005, p.297). While these studies do not give indication of the relative merits of these different methods of feedback, positive consequences are generally seen. ...
... Even experienced teachers can be surprised by student's misunderstandings (Bell & Cowie, 2001;Thissen-Roe et al., 2004), and in learning formative strategies, teachers are better able to use assessment information (Bell & Cowie, 2001;Hand & Prain, 2002). Teachers in these studies draw on a variety of assessment sources to inform their teaching, from students' responses to oral questions (Bell & Cowie, 2001;Black & Harrison 2001a), student interaction with computer simulations (Vendlinski & Stevens, 2002), discussion in group problem solving (Leat & Nichols, 2002), individual products (Hermann & Lewis, 2004), and portfolios (e.g. Barootchi & Keshavarz, 2002). ...
Full-text available
Article
Formative assessment, or assessment for learning, has been championed by assessment specialists and increasingly endorsed by professional organizations. Although it may be particularly beneficial for secondary students, the implementation of formative assessment at the secondary level has met with some resistance. To take stock of the research that has been done in this area, and to consider prospects for further inquiry, a methodical review of recent research was undertaken. Following a systematic selection procedure with clearly specified inclusion criteria, 30 articles, which were published between 2000 and 2005 in refereed journals, were retained for review. A data collection form was used to gather information about the context and methodology of each study. A model of formative assessment that was synthesized from existing research was used as a framework for deductive analysis, and each text was also read inductively, with patterns emerging across the texts. Results show that the research reviewed varies considerably in scope, focus and method, but the international nature of the work is noted, along with a strong interest in Science and a reliance on qualitative methods. Formative assessment is seen as a complex activity, with considerable focus on student involvement in assessment, feedback to students, and explicit learning goals or assessment criteria. Although practical challenges are often raised, the pedagogical potential of formative assessment is reflected in this body of work. Priorities for further inquiry that are manifest in these studies commonly relate to three areas: the educational context of the research, the effectiveness or relative merit of assessment methods, and students' internal processes in formative assessment. In addition, the quiet zones in this analysis suggest several promising avenues, such as a stronger use of student voices, deeper inquiry into the human dynamics that play into formative assessment, and greater consideration of the feasibility issues that teachers face in using formative assessment in secondary classrooms. Appended are: (1) Data Collection Forms (1 of 2) ; (2) Data Collection Forms (2 of 2); and (3) Context of Studies for Selected Articles. (Contains 1 figure.)
... Starting from a constructivist approach, Hermann and Lewis (2004) developed an assessment tool based on time-lines of an adult's life in the form of a geo-chronologic table. They tested the tool in a sample of 9 th grade US students. ...
Full-text available
Thesis
This thesis is the result of two different researches addressing the following issues: Part I: the teaching of Earth Sciences in Italian liceo high schools Part II: the understanding of geological time in a sample of 9th grade students of Friuli Venezia Giulia
... General life experiences can be good sources as well. Hermann and Lewis (2004) suggested that the phases of human life could be a helpful example to use in an analogy for the structure of the geological timescale. Because the phases are partitioned into unequal units, such as childhood, young adulthood, and adulthood, with embedded subunits such as pre-teen and teen, the relational structure of a human timeline can align well with the hierarchical structure of the geologic time scale. ...
Full-text available
Article
Geoscience instructors and textbooks rely on analogy for teaching students a wide range of content, from the most basic concepts to highly complicated systems. The goal of this paper is to connect educational and cognitive science research on analogical thinking with issues of geoscience instruction. Analogies convey that the same basic relationships hold in two different examples. In cognitive science, analogical comparison is understood as the process by which a person processes an analogy. We use a cognitive framework for analogy to discuss what makes an effective analogy, the various forms of analogical comparison used in instruction, and the ways that analogical thinking can be supported. Challenges and limitations in using analogy are also discussed, along with suggestions about how these limitations can be addressed to better guide instruction. We end with recommendations about the use of analogy for instruction, and for future research on analogy as it relates to geoscience learning.
... This framework is used in all activities in this course. In this particular classroom activity, students first use an interview with an older adult to construct a timescale, which they divide into periods and compare timescales among the class (modified after Hermann and Lewis, 2004). Next, students develop a geologic timescale of events provided by the instructor using only their prior knowledge. ...
Full-text available
Article
Effective instruction hinges in part on understanding what prior knowledge students bring to the classroom, and on evaluating how this knowledge changes during instruction. In many disciplines, multiple-choice tests have been developed to gauge student prior knowledge and assess learning. In this study, a 15-item version of the Geoscience Concept Inventory (GCI) was used to assess the prior knowledge and learning of students enrolled in an introductory physical and historical geology course specifically designed for preservice elementary (K-8) teachers. Gains (pretest to posttest) among participants (n = 122) averaged 4%, similar to gains reported elsewhere. However, gains among participants enrolled in revised course sections (n = 84) averaged 7-8%. Detailed analysis shows that statistically significant gains occurred on test items related to geologic time, earthquakes, radiometric dating, and tectonics. Items for which the greatest gains were observed correlate with teaching method; classroom activities coupled with discussion and supplemental reading appear most effective in increasing student knowledge. Our interpretation of the GCI results suggests that students need multiple opportunities to work with geologic concepts in a variety of formats, and provides further evidence of the persistence of student prior knowledge in specific topics.
Article
The Finger Lakes area has some of the most unique geologic features in New York State including much evidence of the impact that glaciers have had on this environment. The area is rich in Devonian and Silurian era fossils, drumlins, U-shaped valleys, and glacial erratics. With all of this evidence it is easy to imagine a class of students outside in the environment examining these structures and developing conclusions about their origin. However, students in the Finger Lakes area are generally taught about the geology of the area using traditional techniques utilizing technology and diagrams in the classroom. In this study, students were separated into a control group and an experimental group. The control group was exposed to traditional teaching methods including a PowerPoint presentation and a laboratory activity on the football field. The experimental group was exposed to a field study that included “EarthCache” type assignments where students are asked to use Global Positioning Systems to find evidence of past geologic events and use it to answer questions. Scores on a pre- and posttest using the “art of the sentence” techniques found in Doug Lemov’s Teach Like a Champion were compared for overall growth of knowledge. Students in both groups increased the scores, as expected. However, students in the experimental group increased their scores more than the control group in every concept that was focused on in this study, and increased 15% higher overall when compared to the growth of the control group students. The students who experienced the field study were more sophisticated with their usage of evidence to support their claims made in the posttest when compared to the control group’s posttest usage of evidence, posting over a 35% score increase. Students that experienced the field study showed a higher understanding of the concepts focused on in this study. Therefore, this study provides evidence that a field study designed with a specific purpose, such as an EarthCache, can provide students with a deeper understanding of the geology of the Finger Lakes area. This deeper understanding can be attributed to the personal connection students had made with the environment while being driven by their natural curiosity of the natural world.
Article
Earth science is the study to explore the planet in which we live. Among these earth science geology of the area it can be the most critical and important study. However, because of the size and scope is too broad temporal spatial eurona covered in geology is true that many students find difficult about the geology field. In this study, in conjunction with landscape formation of geologic time for the concept to be among the core areas of Geology examined the concept and recognize it as the destination for high school students. Is a test tool for the analysis was adapted for use by Jolley (2010) has developed LIFT (The Landscape Identification and Formation Test). Currently we fix the strip to match the country through a validity check of the curriculum. Results of the study were as follows: First, the ability to check the landscape and formation is expected to estimate the time and the liberal arts students was higher than the natural science students. The reason for this seems to be the influence of learning geographical subjects. Second, the concept of geological time was found to lack both natural science and liberal arts students. The reason is that the students in the previous process because it deals with the concept of geologic time from the top of Earth Science Education II seems to be because there was no chance of learning about geological time. Third, the results confirm the confidence of the students surveyed in the landscape formation time natural science students was higher than liberal arts students. The research measured gender boys higher than girls. Fourth, the students on the landscape and geological time was found to have a number of misconceptions. This appears to be due to the students to feel difficulty in thinking of the concept because the need to understand the abstract geologic time. Therefore, it is necessary just to hold misconceptions about the concept of geology students have through the study of the landscape and geological time.
Article
College student conceptions of the scale of geologic time and the relationships between time and geological or biological events were evaluated through interviews, open-ended questionnaires, and student generated timelines collected from four institutions. Our data indicate students hold a number of alternative conceptions about the Earth's formation and the appearance of life, and these ideas are remarkably consistent across institutions. Transferability of these findings was evaluated via comparison with Geoscience Concept Inventory questions related to geologic time collected from 43 institutions nationwide. Detailed evaluation of student timelines reveals a notable disconnect between the relative relationships between the age of the Earth, the time required for the origin of the first life forms (prokaryotes), and the evolution of dinosaurs and humans. Students generally placed these events in the correct relative order, but had a poor understanding of the scale of time between events. Intriguingly, timelines can be mapped onto ternary diagrams, and the relationship between ternary diagram zoning and specific ideas of geologic time is explored. We found that some students, for example those with a young Earth perspective, map onto specific conceptual zones on ternary diagrams.
Article
In this study, assessment items to examine geocognition on plate tectonics were developed and applied to middle and high school students and college students. Conceptual constructs on plate tectonics are Earth interior structure, specific geomorphology, and geologic phenomena at each plate boundary. Construct for geocognition included temporal reasoning, spatial reasoning, retrospective reasoning, and system thinking. Pictorial data in each item were all obtained from GeoMapApp. Students` responses to the items were analyzed and measured cross-sectionally by Rasch model, which distinguishes persons` ability levels based on their scores for all items and compared them with item difficulty. By Rasch model analysis, Wright maps for middle and high school students and college students were obtained and compared with each other. Differential Item Functioning analysis was also implemented to compare students` item responses across school grades. The results showed: 1) Geocognition on plate tectonics was an assessable construct for middle and high school students in current science curriculum, 2) The most distinguished geocognition factor was spatial reasoning based on cross sectional analysis across school grades, 3) Geocognition on plate tectonics could be developed towards more sophisticated level through scaffolding of relevant instruction and earth science content knowledge, and 4) Geocognition was not a general reasoning separated from a task content but a content-specific reasoning related to the content of an assessment item. We proposed several suggestions for learning progressions for plate tectonics and national curriculum development based on the results of the study.
Full-text available
Article
Existing K-8 Earth Science curricula often require a middle school level of understanding. With tangible evidence, however, Fourth grade students are able to grasp complex earth science concepts. Given the complex, abstract modeling activities needed to comprehend geosciences, what is the most effective way to teach and understand these complexities at the fourth, fifth, and sixth grade levels? What should teachers do with curricula that do not provide enough tangible evidence? Teaching geosciences must not only mirror the language distinction between fifth grade students’ ability to know and describe and eighth grade students’ ability to identify and explain geological processes, but must also be enhanced with tangible evidence. Only then will it become increasingly clear that changes on the earth’s surface can be slow and gradual (such as weathering and erosion, glaciers, etc.) or sudden and catastrophic (such as earthquakes, tsunamis, etc.). Curricula units must be designed to develop interest in subjects that many students do not have access to and/or receive on a regular basis with real-life evidence. Emphasis on inquiry-based curricula, increased hands-on experiences, and student accessibility to tangible evidence, coupled with science standards that reflect such an emphasis, make teaching and learning more accessible to a greater audience. Based on the results of this study, I recommend the following five actions to integrate tangible evidence into earth science curricula and challenge students to grapple with complex geoscience modeling. First, teachers must seek tangible examples and/or outcrops in the surrounding environment (including the urban environment). Further, teachers must advocate classroom excursions to such locations on a regular basis to supplement classroom learning; school administrators must provide such opportunities and recognize the importance of tangible evidence in the classroom (and should be encouraged to provide additional classroom help on a regular basis). Second, teachers must adapt curricula as needed to increase student understanding, especially as it pertains to local understanding of the immediate environment. Third, field trips that involve differing classroom teachers provide myriad opportunities to combine learning targets; for example, a social studies field trip to a local Native American museum that stops at an exposed road cut along the way emphasizes how the two are related. Fourth, in the absence of immediate exposure to outcrops schools can construct an artificial outcrop from existing rocks in situ and/or external sources and fabricate an artificial rock outcrop where physical field trips to naturally occurring exposures are difficult to arrange. Finally, integration of technology suggested by the Apple Education iLife Project provides myriad opportunities for student assessment and ways to integrate tangible learning experiences while at the same time facilitates their own creativity.
Full-text available
Article
A critical element of the earth sciences is reconstructing geological structures and systems that have developed over time. A survey of the science education literature shows that there has been little attention given to this concept. In this study, we present a model, based on Montagnero's ([1996]) model of diachronic thinking, which describes how students reconstruct geological transformations over time. For geology, three schemes of diachronic thinking are relevant: 1. Transformation, which is a principle of change; in geology it is understood through actualistic thinking (the idea that present proceeses can be used to model the past). 2. Temporal organization, which defines the sequential order of a transformation; in geology it is based on the three-dimensional relationship among strata. 3. Interstage linkage, which is the connections between successive stages of a transformation; in geology it is based on both actualism and causal reasoning. Three specialized instruments were designed to determine the factors which influence reconstructive thinking: (a) the GeoTAT which tests diachronic thinking skills, (b) the TST which tests the relationship between spatial thinking and temporal thinking, and (c) the SFT which tests the influence of dimensional factors on temporal awareness. Based on the model constructed in this study we define the critical factors influencing reconstructive thinking: (a) the transformation scheme which influences the other diachronic schemes, (b) knowledge of geological processes, and (c) extracognitive factors. Among the students tested, there was a significant difference between Grade 9-12 students and Grade 7-8 students in their ability to reconstruct geological phenomena using diachronic thinking. This suggests that somewhere between Grades 7 and 8 it is possible to start teaching some of the logical principles used in geology to reconstruct geological structures.
Article
As part of a continuing research program on the understanding of geological time (deep time) across society, a total of 51 in-service teachers of 7- to Ii-year-old children was studied in relation to their orientations toward geoscience phenomena in general and deep time in particular. The first purpose of the research was to identify the nature of idiosyncratic conceptions of deep time: a cognitive deep time framework of pivotal gee-events. The second was to propose a curricular Deep Time Framework that may form the basis for constructivist approaches to in-service and pre service teacher training which places deep time center stage. Three research questions were posed, addressing: (1) perceptions of geoscience phenomena and teachers' actual encounters with these in the classroom; (2) conceptions of deep time; and (3) approaches to teaching two curriculum areas (history and geology) which involve the interpretation of material evidence to reconstruct the past. Results enable the selection of 20 geoscience phenomena to be located in relation to teachers' interests and classroom encounters, those of high interest and high encounters being proposed as pivotal areas for further attention in teacher training. Results also reveal that inservice teachers conceive events in the geological past (geo-events) as having occurred in three distinct clusters: extremely ancient; moderately ancient; and less ancient. Within each category there is a strong lack of consensus on time-of-occurrence. Results suggest that primary teachers exhibit greater imagination in their teaching of history compared with geology and that aspects of deep time and past environments are not perceived as being of any great significance in the interpretation of geological specimens. (C) 2001 John Wiley & Sons, Inc.
Article
Rubrics, scoring guides, and performance criteria help define important outcomes for students. Well crafted rubrics help teachers define learning targets so that they can plan instruction more effectively, be more consistent in scoring student work, and be more systematic in reporting student progress. Rubrics can generally be divided into holistic or analytical trait rubrics, and task-specific or general rubrics. A third dimension that distinguishes rubrics is the number of score points. Rubrics must be of high quality in order to have positive effects in the classroom. A metarubric, a rubric for rubrics, has four traits: content, clarity, practicality, and technical soundness. Attachments discuss building a performance rubric and contain a discussion of the metarubric. A final attachment (figure 5) presents seven strategies for using criteria as a teaching tool. (SLD)
Chapter
his article is about classroom assessment--not the kind of assessments used to give grades or to satisfy the ac- countability demands of an external authority, but rather the kind of assessment that can be used as a part of instruction to support and enhance learning. On this topic, I am especially interested in engaging the very large num- ber of educational researchers who participate, in one way or another, in teacher education. The transformation of as- sessment practices cannot be accomplished in separate tests and measurement courses, but rather should be a central concern in teaching methods courses. The article is organized in three parts. I present, first, an historical framework highlighting the key tenets of social efficiency curricula, behaviorist learning theories, and "sci- entific measurement." Next, I offer a contrasting social- constructivisbconceptual framework that blends key ideas from cognitive, constructivist, and sociocultural theories. In the third part, I elaborate on the ways that assessment prac- tices should change to be consistent with and support social-
Reconstructing the geologic timeline: Adding a constructivist slant to a classical activity, The Science Teacher, v. 69
  • D Hemler
  • T Repine
Hemler, D. & Repine, T., 2002, Reconstructing the geologic timeline: Adding a constructivist slant to a classical activity, The Science Teacher, v. 69, p. 32-35.
Developing and using cfassroom assessments
  • A Oosterhof
Oosterhof, A., 1999, Developing and using cfassroom assessments, 2nd ed, New Jersey, Prentice Hall.
Classroom assessment
  • P W Airasian
Airasian, P. W., 1997, Classroom assessment, 3rd ed, McGraw-Hill.