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Laboratory work in distance education

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Abstract

A major concern in distance education is how to overcome the problems associated with laboratory components of courses. In this paper we review the general importance of laboratory work for students, summarise the advantages and disadvantages of conventional and home‐study laboratory activities, describe five basic alternatives to conventional laboratories, and outline three areas where improvements need to be made in the offering of laboratories at a distance.
DISTANCE
EDUCATION
Volume 3. Numher 2. 19X2
Laboratory work in distance education
Robert G. Holmberg and Trilochan S. Bakshi
Laboratory work in distance education
Robert G. Holmberg and Trilochan S. Bakshi
A major concern in distance education is how to overcome the problems
associated with laboratory components of courses. In this paper we
review the general importance of laboratory work for students, summa-
rise the advantages and disadvantages of conventional and home-study
laboratory activities, describe five basic alternatives to conventional
laboratories, and outline three areas where improvements need to be
made in the offering of laboratories at a distance.
GENERAL IMPORTANCE OF LABORATORY WORK
Courses that can use laboratory activities range from elementary to
graduate school level. They include courses related to the basic sciences
of biolob'Y', chemistry, geology and physics; courses in applied sciences
or technology such as various aspects of agriculture, engineering,
computing and health sciences; courses in social sciences such as psy-
cholob'Y and anthropology; and -if we stretch the definition of the
term 'laboratory' (usually defined as a place where one docs experi-
ments) we could include certain courses that use language 'laboratories'
or special workshops connected with fine arts (e.g., pottery, weaving,
sculpture).
The benefits or laboratory work are the same for all students whether
they be children or adults studying in schools or in their hOllles.
LaboLI(ory activities arc used to:
.introduce new concepts or review those studied previously;
.provide direct experience with laboratory equipment, techniques and
speCllllens;
198.
Robert G. Holmberg and Trilochan S. Bakshi
.provide opportunities to test hypotheses related to the associated
cou rses;
.allow practice in practical problem-solving, that may include the use
of various scientific methods; and
.increase intellectual stimulation about or appreciation for the subject
involved (Holt et aI., 1979; Rasmussen, 1970; Shulman and Tamil',
1973).
CONVENTIONAL vs HOME STUDY LABORATORY
ACTIVITIES: ADVANTAGES AND DISADV ANTAGES
There are six major considcrations that must be taken into account
when any type of laboratory activity is prcpared, namely:
.the target audience (i.c., age, sex, previous education and experience.
as well as social and cultural environments of the students who are
likely to take the course);
.the subject matter or content of the course;
.the pedagogical considerations of how the course should be taught;
.economic considerations;
Target audience Subject matter
Technology Pedagogy
Safety Economics
Figure I. Relationships between six major aspects that affect
the planning of any laboratory work for students
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Distance Education Vol. 3, No. 2. 1l}~2
. safety of the students as well as others who may come into contact
with the laboratory materials; and
.the current state of technology in terms of available equipment.
All of these factors arc in lerdependen t (Figure 1) bu t their relative
importance depends upon one's point of view. For example, if you arc
a physics teacher you may consider the subject matter as most impor~
tant. However, if you are in charge of finances, you may regard economic
considerations to be paramount. The emphasis placed on these factors
varies with the people involved. .
Fixed
time
and
place
Conventional... Audio-tutorial... Home-Study
Flexible
time
and
place
Figure 2. Laboratory activities viewed as a continuum in terms of
tlexibility of students' use of time and space
Laboratory activities also can be viewed (Figure 2) as a continuum that
ranges from conventional laboratories where students work in groups
at fixed times and places, through audio~tutorial methods that allow
more flexibility in time, to home~study approaches that involve indivi~
dual students working at times and locations of their convenience. In
this paper we consider only the two extremes of this continuum, i.L,
conventional and home-study activities.
For conventional laboratories, there arc the following potential advan-
tages: economies related to mass instruction, immediate feedback for
students who encounter problems, discussion between students, direct
supervision of student safety, student access to expensive or even
unique equipment and specimens, the possibility of quick changes of
plans if something goes wrong or is not available, and the familiarity
of the process for both students and teaching staff.
The major disadvantage of convention;J laboratories is the considerable
restriction that they impose upon students trying to get to the same
place at the same time. In addition. there arc the high costs of provid~
ing, at nearly one time, su fficien t labo ratory space, equip men t and staff
for all students. These logistic and financial restrictions greatly limit
what students can achieve in a course.
200.
Robert G. Holmberg and Trilochan S. Bakshi
Home laboratory activities provide some distinct advantages to stu.
dents. The most important advantage is related to student convenience.
As with other a$pects of distance education, home laboratory activities
allow studen ts to: avoid time-wasting journeys; stud y when and where
they wish to so that they can fulfill job, family and social commitments;
work at their own pace; and repeat observations as necessary. This
method of instruction also makes laboratory-related education available
to persons who normally could not attend traditional classes. Such per
sons include those who live in remote areas, have health problems, are
confined in prisons, or travel a great deal (e.g., those in sales or in the
armed forces) (Holmberg, 1977). In addition, activities done at home
allow students the opportunities to extend observations over relatively
long periods. Finally, the capital costs of buildings and equipment are
much less for preparing and offering home labs than for conventional
teaching methods.
There are, however, three major disadvantages with laboratory activities
done at home. Firstly, developmental costs usually exceed those associ-
ated with conventional laboratory work. Even seemingly minor items,
such as packaging, may require substantial amounts of planning and
field trials before problems, such as safe transport, economically accept-
able materials and inventory concerns, can be overcome. Secondly,
there are the problems of safety. In considering safety one must not
only consider the students who do the experiments, but also such
people as those who assemble, store, ship and deliver the materials as
well as children who may be present in the students' homes. Thus, stu-
dents and many of the institution's staff have to learn appropriate pre-
cautions for eye and skin protection, storage and disposal methods, the
rudiments of first-aid, and how to handle accidental spills and put out
fires. Finally, there are the difficulties involved in obtaining trans-
ferability of courses that use these, still rather unconventional, methods
of delivery.
To demonstrate that these problems are real, all one has to do is
examine the course offerings of institutions engaged in distance eduGI.
tion. For example, in Canada and the United States there is a total of
seven t y-five colleges and universities that offer, at a distance, t wen t y or
more three-credit courses (Canadian Association for University Con-
tinuing Education, 1980; Hunter, 1980). However, less than twenty-
seven per ccnt of thesc offcr a 'substantial' (i.e., a total of five or morc
courses in the fields of biology, chemistry, geology or physics) numbcr
of courses that may involve laboratory work (FibJl.trC 3).
201.
Distance Education Vol. 3, No.2, 191-\2
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Figure 3. Distribution of institutions in Canada and the United States
that offer twenty or more college or university courses at a distance.
Those institutions that offer a 'substantial' number of laboratory courses
are shown as solid squares.
This should not be interpreted to mean that the difficultues of offering
laboratory activities at a distance are insurmountable for most institu.
tions. Indeed, we think that courses which require laboratory work are
feasible for nearly all institutions that offer programmes in distance
education. Thus even ;~ early as 1925, rural students in New Zealand
received laboratory materials for home learning (Shelley, 1932).
Currently the largest university in the United Kingdom, the Open Uni.
versity, uses home laboratory activities to help its students acquire
laboratory experiences. And now, these methods are being used in a
number of developing countries (Side and Hacker, 1977).
202.
Robert G. Holmberg and Trilochan S.
Bakshi
ALTERNATIVES TO CONVENTfONAL LABORATORIES
In distance education, there are five basic alternatives to conventional
laboratories. We will first outline these al ternatives, in order of increasing
developmental costs, and then explore them a little further with a
specific example.
The first alternative is simply to eliminate all laboratory activities. This
is the easiest, cheapest and, unfortunately, the most common choice
made by institutions that begin to deliver courses at a distance. Though
this alternative can be justified, it has serious long term consequences
for the school's curriculum.
If an institution has on-campus as well as external students, the next
easiest alternative is to make the existing laboratory facilities available
to both types of students. Often this simply means opening the labora,
tories at times when on-campus students are not using the facilities.
When the home-study student is located beyond a reasonable travelling
distance from the institution, the next alternative is to use local
laboratory facilities. However, there are problems with this alternative.
They include things such as liability concerns for possible damage done
by students, conflicts with cleaning staff who often work in the same
'off-hours' as the distance education students, and accessibility to the
laboratory by public and private transportation.
The fourth alternative is to send the laboratory to the students rather
than have the students come to the laboratory. There are many possi-
bilities within this alternative. The most common method is the prepara-
tion of a laboratory kit. The kit may contain all items needed by the
students or it may contain only those things that students can not
readily obtain locally. These kits are usually sent via the local postal
system. However, as most postal systems restrict the mailing of many
commonly-used chemicals, such as acids and flammable solvents, com-
mercial carriers or the institution's own transport facilities may have to
be used.
The fifth alternative is that of substitution. In its simplest fonn, substi-
tution may mean that instructors provide sets of data for students to
analyse and speculate upon. However, substitution often im'olves the
use of various audio/visual materials that allow students to ohservc and
record information generated by otherwisc inaccessible cquipment.
Substitu tions also include the use of compu ter simula t in ns. These
simulation activities allow students to examine phenomcna (e.g.,
baIlistics, chemical reactions and genetic crosses) that m;,,:,' involve
203.
Distance Education Vol. 3, No, 2,1982
dangerous procedures, inordinate amollnts of time, or equipment more
expensive than computer costs (see Smith and Sherwood, 1976).
We will now explore these five alternatives further by discussing an
example of an expensive and delicate piece of laboratory equipment
the compound light microscope. A microscope is almost indispensable
in a biology laboratory so much so that the use or non-use of a micro-
scope often determines if a biology course will be acceptable to other
institutions for credit transfer. Though a microscope is a fairly specialis-
ed piece of equipment, alternatives are available and we think that
modern technology can also be used to develop alternatives for other
'indispensable' laboratory equipment such as balances, chemical models,
optical benches, spectrophotometers, and pH meters.
The first of the five alternatives is to eliminate the microscope. The
crucial question in making this decision is to determine whether it is
sufficient for the students to know how a microscope works, what its
capabilities and limitations are rather than how it is used.
If it is deemed important that students know how to use a microscope,
it must then be asked whether the students can come to a central
laboratory on certain evenings, on week-ends, or in the summer.
The third alternative is to use some local facility that already has micro-
scopes or can store them, and is willing to allow students access. These
facilities may be available in the laboratories of secondary schools,
technical schools, industrial complexes, and hospitals involved in teach-
mg nurses.
The fourth alternative includes the possibil;ties of sending to students
basic components for assembly, sending conventional microscopes, or
sending special portable microscopes.
Simple plastic lenses and cardboard tubes have been used by students
to learn the fundamentals of microscope construction and theory
(Norberg and von Blum, 1975). However, it is also possible for students
to build fairly sophisticated microscopes in the same way that some
electronic service people learn how to build radios, oscilloscopes, and
televisions from components sent to their homes by commercial institu-
tions. .
Conventional equipment may be sent by mail or delivered to the stu-
dents by truck, boat or even plane. For example, in British Columbia,
Canada, North Island College uses trucks and a boat to transport specialis-
ed equipment to students in remote areas of Vancouver Island. In effect,
204.
Robert G. Holmberg and Trilochan S. 13akshi
these vehicles are travelling laboratories.
Portable microscopes are not common but arc available in various forms
as 'field' microscopes from commercial manufacturers. Also, the British
Open University designed and manufactured its own portahle micro-
scope for use by its students.
The fifth possibility, that of substitution, can be used as a preliminary
step in teaching microscope use or as a complete substitution for the
provision of actual microscopes. Different substitutions take various
fonns such as transparencies, filmstrips, microfiche cards, films, or
videotapes. There are several commercial devices that can use the first
three kinds of materials to provide inexpensive colour illustrations.
However, mechanisms for showing motion are still very expensive.
We believe that if teachers explore these five alternative solutions along
the lines indicated above for a microscope, many of the problems
associated with offering laboratory activities at a distance can be over-
come.
FURTHER IMPROVEMENTS
Before laboratory work can assume its full and proper place in distance
education, there are three major areas in which improvements need to
be made.
The first is increased communication and co-operation between institu-
tions involved in developing alternatives to conventional laboratory
instruction. It is oft<.n the case that one institution will develop a set
of procedures or a home lab kit but the work has to be redone else-
where because other institutions either do not know of the develop-
ments or cannot obtain official pennission to use the materials (e.g.,
proper copyright pennissions were not obtained when the materials
were developed).
The second area, that has been briefly mentioned above, is the problem
of credit transfer of distance education courses to conventional and,
even, non-conventional institutions. Though appropriate courses for
students at a distance may be somewhat different in their appro~lch and
delivery, the question remains as to whether or not they will be accept-
able to other institutions for transfer of credits. Even though courses
delivered at a distance have a long and successful history, many people
still regard them as inferior and unacceptable.
The third area involves technological improvements that should decrease
205.
Distance Education Vol. 3, No.2, 1982
costs and increase efficiencies. This includes things such as miniaturisa-
tion of electrical apparatus and mass production of specialised equip-
ment. A specific example is the possible use of hand-held programmable
calculators for courses involving statistics and calculus. This area also
includes improved methods of communication between students and
staff of the teaching institution which, in turn, will improve the offer.
ing of all aspects of the learning process (Kelly and Anandam, 1978).
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... institutions when offering science courses because of the fewer occasions for students to be on campus where laboratory facilities, relevant equipment, and teaching staff are provided (Holmberg & Bakshi, 1982). Nonetheless, the literature reveals impressive cases of teaching science at a distance, including such subjects as Physcial Geology (McCartney, Kimball, & Swetname 1992), Chemistry (Kennepohl & Last, 2000), Human Biology (Naber & LeBlanc 1994), and Physics (Atan et al, 2002). ...
... Each method has inherent advantages and disadvantages, and thus it becomes essential for distance education program providers to select one, or an array of methods, that can best suit their students under specific individual or environmental circumstances. Besides the analysis of target students, Holmberg & Bakshi (1982) suggested the nature of subject matter, pedagogical considerations of how the course should be taught, economic considerations, safety concerns, and available equipment of the institution as points of discussions when any laboratory activity, among other types of practical work, is prepared for distance students. The relative importance of these factors is, after all, dependent on one's point of view. ...
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  • C E Holt
  • P Abramoff
  • Wilcox Jr
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Holt, C.E., Abramoff, P., Wilcox Jr., L.V. and Abell, D.L. (1969) Investigative laboratory pro-grammes in biology. Bioscience 19, 12, 1104-1107.
Instruction at a distance is personalised through tech. nology
  • J T Kelly
  • K Anandam
Kelly, J.T. and Anandam, K. (1978) Instruction at a distance is personalised through tech. nology. Journal ofPersonalised Instruction 3, 3,162-164.
Take-home laboratory activities: one answer to the time and space problem
  • A M Norberg
  • R Blum
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