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An analysis of students' academic and social scores compares a Montessori school with other elementary school education programs.
DOI: 10.1126/science.1132362
, 1893 (2006); 313Science
et al.Angeline Lillard,
THE EARLY YEARS: Evaluating Montessori (this information is current as of December 18, 2006 ):
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ontessori education is a 100-year-
old method of schooling that was
first used with impoverished pre-
school children in Rome. The program con-
tinues to grow in popularity. Estimates indi-
cate that more than 5000 schools in the
United States—including 300 public schools
and some high schools—use the Montessori
program. Montessori education is character-
ized by multi-age classrooms, a special set of
educational materials, student-chosen work
in long time blocks, collaboration, the
absence of grades and tests, and individual
and small group instruction in both academic
and social skills (1). The effectiveness of
some of these elements is supported by
research on human learning (2).
We evaluated the social and academic
impact of Montessori education. Children
were studied near the end of the two most
widely implemented levels of Montessori
education: primary (3- to 6-year-olds) and
elementary (6- to 12-year-olds). The Mon-
tessori school we studied [located in Mil-
waukee, Wisconsin (3)], which served
mainly urban minority children, was in its
ninth year of operation and was recognized
by the U.S. branch of the Association
Montessori Internationale (AMI/USA) for
its good implementation of Montessori
principles (4).
Because it was not feasible to randomly
assign children to experimental and control
educational groups, we designed our study
around the school lottery already in place.
Both the experimental and the control group
had entered the Montessori school lottery;
those who were accepted were assigned to
the experimental (Montessori) group, and
those who were not accepted were assigned
to the control (other education systems)
group. This strategy addressed the concern
that parents who seek to enroll their child in
a Montessori school are different from par-
ents who do not. It is crucial to control for
this potential source of bias, because parents
are the dominant influence on child out-
comes (5).
We contacted parents of children who had
entered the Montessori school lottery in
1997 and 2003 and invited them to be in the
study. All families were offered $100 for
Because the lottery, which was con-
ducted by the school district, was random,
the Montessori and control groups should
contain similar children. Ninety percent of
consenting parents filled out a demographic
survey. Parents from the Montessori and
control groups had similar average incomes
($20,000 to $50,000 per year) at each stu-
dent age level. This addressed a concern
with a retrospective lottery loser design that
the final samples might be different for rea-
sons other than the treatment. Another vari-
able, ethnicity, was not surveyed because
parent income contributes more to child out-
comes than does ethnicity (6). We were also
concerned that requesting ethnicity data
would reduce participation in this racially
divided city.
Overall, 53 control and 59 Montessori stu-
dents were studied (table S1). The 5-year-old
group included 25 control and 30 Montessori
children, and the 12-year-old group included
28 control and 29 Montessori children.
Gender balance was imperfect, but gender
did not contribute significantly to any of the
differences reported here. Children at the
Montessori school were drawn from all six
classrooms at the primary level and all four at
the upper elementary level. The control chil-
dren were at non-Montessori schools: 27 pub-
lic inner city schools (40 children) and 12
suburban public, private/voucher, or charter
schools (13 children). Many of the public
schools had enacted special programs, such
as gifted and talented curricula, language
immersion, arts, and discovery learning.
Children in both groups were tested for
cognitive/academic and social/behavioral
skills that were selected for importance in
life, not to examine specific expected effects
of Montessori education. Our results re-
vealed significant advantages for the Mon-
tessori group over the control group for both
age groups.
Results: 5-Year-Olds
Cognitive/Academic Measures. Seven scales
were administered from the Woodcock-John-
son (WJ III) Test Battery (7). Significant dif-
ferences favoring Montessori 5-year-olds were
found on three WJ tests measuring academic
skills related to school readiness: Letter-Word
Identification, Word Attack (phonological de-
coding ability), and Applied Problems (math
skills) (see chart, left). No difference was
expected or found on the Picture Vocabulary
test (basic vocabulary) because vocabulary is
highly related to family background variables
(8). Two WJ tests of basic thinking skills—
Spatial Reasoning and Concept Formation—
also showed no difference.
Five-year-olds were also tested on execu-
tive function, thought to be important to suc-
cess in school. On one such test, children
were asked to sort cards by one rule, switch
to a new rule, and (if they did well) then
switch to a compound rule. Montessori chil-
dren performed significantly better on this
test. A test of children’s ability to delay grat-
ification (a treat) did not indicate statisti-
cally significant differences.
Social/Behavioral Measures. Children were
given five stories about social problems, such
as another child hoarding a swing, and were
asked how they would solve each problem (9).
An analysis of students’ academic and social scores compares a Montessori school with
other elementary school education programs.
Evaluating Montessori Education
Angeline Lillard
* and Nicole Else-Quest
Mean z score
WJ letter-word
WJ word attack
WJ applied math
Card sort (executive function)
False belief (social cognition)
Refers to justice
Positive shared play
Ambiguous rough play
Results for 5-year-olds. Montessori students ach-
ieved higher scores [converted to average z scores
(18)] for both academic and behavioral tests.
Department of Psychology, University of Virginia P.O.
Box 400400, Charlottesville, VA 22904, USA.
of Psychology, University of Wisconsin, Madison, WI
53202, USA.
*Author for correspondence. E-mail:
Published by AAAS
on December 18, 2006 www.sciencemag.orgDownloaded from
Montessori children were significantly more
likely (43% versus 18% of responses) to use a
higher level of reasoning by referring to justice
or fairness to convince the other child to relin-
quish the object. Observations at the play-
ground during recess indicated Montessori
children were significantly more likely to be
involved in positive shared peer play and sig-
nificantly less likely to be involved in rough
play that was ambiguous in intent (such as
wrestling without smiling).
The False Belief task was administered to
examine children’s understanding of the
mind (10). Recognition that people repre-
sent the world in subjective as well as objec-
tive ways is a landmark achievement in
social cognition (11). Social negotiation and
discussion about mental states leads to this
advance in children (12). Whereas 80%
(significantly more than chance) of the
Montessori 5-year-olds passed, the control
children were at chance, with 50% passing.
Results: 12-Year-Olds
Cognitive/Academic Measures. Twelve-year-
olds were given 5 minutes to complete a story
beginning “____ had the best/worst day at
school.The Montessori students’ essays were
rated as significantly more creative and as
using significantly more sophisticated sentence
structures (see chart, below). Control and
Montessori essays were similar in spelling,
punctuation, and grammar. Unlike the 5-year-
olds, the 12-year-olds did not perform differ-
ently on the WJ tests. This is surprising,
because early reading skills normally predict
later reading (13). Either the control group had
“caught up” by age 12 to the
Montessori children, or the 12-
year-old Montessori children
were not more advanced in
these early reading skills when
they were 5. If the latter, one
possible explanation is that the
12-year-olds started at the
school when it was in its third
year. The Montessori method
relies on peer teaching and
modeling, so those who are in
the early classes of a new school
lack some advantages relative
to those who begin later.
Social/Behavioral Measures.
As a social skills test, 12-year-
olds read six stories about
social problems (such as not
being asked to a party) and
were asked to choose among
four responses. Montessori
12-year-olds were significantly
more likely to choose the posi-
tive assertive response (for example, ver-
bally expressing one’s hurt feelings to the
host). On a questionnaire regarding their
feelings about school, Montessori children
indicated having a greater sense of commu-
nity, responding more positively to items
such as, “Students in my class really care
about each other” and “Students in this class
treat each other with respect.
Benefits of Montessori Education
On several dimensions, children at a public
inner city Montessori school had superior
outcomes relative to a sample of Montessori
applicants who, because of a random lottery,
attended other schools. By the end of kinder-
garten, the Montessori children performed
better on standardized tests of reading and
math, engaged in more positive interaction on
the playground, and showed more advanced
social cognition and executive control. They
also showed more concern for fairness and
justice. At the end of elementary school,
Montessori children wrote more creative
essays with more complex sentence struc-
tures, selected more positive responses to
social dilemmas, and reported feeling more
of a sense of community at their school.
These findings were obtained with a lottery
loser design that provides control for parental
influence. Normally parental influence (both
genetic and environmental) dominates over
influences such as current or past school and
day-care environments. For example, in the
large National Institute of Child Health and
Human Development (NICHD) study of early
child care, correlations between parenting
quality and WJ early academic
tests had effect sizes compara-
ble to those seen here, whereas
school effects were much smaller
(5). An evaluation of Success
for All, considered a highly suc-
cessful reading intervention,
reported a quarter of a standard
deviation as its largest effect
size (for Word Attack) in a
randomized field trial, and
stated that it was equal to a
4.69-month advance in reading
skills (14). Stronger effects are
often found in the first years
of pilot programs when re-
searchers are involved in
implementation of their own
programs (15), termed the “super-
realization effect” (16). In our
study, the school did not antici-
pate an evaluation. Especially
remarkable outcomes of the
Montessori education are the
social effects, which are generally dominated
by the home environment (17).
Future research could improve on the
research design here by following lottery par-
ticipants prospectively and by tracking those
who drop out and examining their reasons. It
would be useful to replicate these findings in
different Montessori schools, which can vary
widely. The school involved here was affili-
ated with AMI/USA, which has a traditional
and relatively strict implementation. It would
also be useful to know whether certain com-
ponents of Montessori (e.g., the materials or
the opportunities for collaborative work) are
associated with particular outcomes.
Montessori education has a fundamen-
tally different structure from traditional edu-
cation. At least when strictly implemented,
Montessori education fosters social and aca-
demic skills that are equal or superior to those
fostered by a pool of other types of schools.
References and Notes
1. M. Montessori, The Montessori Method (Schocken,
New York, 1964).
2. A. S. Lillard, Montessori: The Science Behind the Genius
(Oxford Univ. Press, New York, 2005).
3. Milwaukee Public Schools
4. Association Montessori Internationale (www.montessori-
5. NICHD Early Child-Care Research Network, Harvard Ed.
Rev. 74, 1 (2004).
6. G. J. Duncan, W. J. Yeung, J. Brooks-Gunn, J. R. Smith,
Am. Soc. Rev. 63, 406 (1998).
7. K. S. McGrew, R. W. Woodcock, Woodcock-Johnson III
Technical Manual (Riverside Publishing, Itasca, IL, 2001).
8. B. Hart, T. Risley, Meaningful Differences in the Everyday
Experience of Young American Children (P. H. Brookes,
Baltimore, MD, 1995).
9. K. H. Rubin, The Social Problem Solving Test–Revised
(Univ. of Waterloo, Waterloo, MI, 1988).
10. H. Wimmer, J. Perner, Cognition 13, 103 (1983).
11. C. Zimmer, Science 300, 1079 (2003).
12. J. Amsterlaw, H. Wellman, J. Cogn. Dev. 7, 139 (2006).
13. A. E. Cunningham, K. E. Stanovich, Dev. Psych. 33, 934
14. G. D. Borman et al., Am. Ed. Res. J. 42, 673 (2005).
15. M. W. Lipsey, Ann. Am. Acad. Polit. Soc. Sci. 587, 69 (2003).
16. L. J. Cronbach et al., Toward Reform of Program
Evaluation: Aims, Methods, and Institutional
Arrangments (Jossey-Bass, San Francisco, 1980).
17. NICHD Early Child-Care Research Network, Am. Ed. Res. J.
42, 537 (2005).
18. The z-score conversion was used for the graph to give all
tests the same metric. A z score sets the mean (in this
case of the entire sample) at 0, one standard deviation
above the mean at 1.68, and one standard deviation
below the mean at –1.68.
19. Funding was provided by the Jacobs and Cantus Foundations
and sabbatical fellowships from the Cattell Foundation and
the University of Virginia to A.L. J. DeLoache, B. Detmer,
L. Ma, A. Pinkham, R. Tai, and J. van Reet provided helpful
comments, and E. Turkheimer provided valuable statistical
advice. We thank the Milwaukee schools that participated;
the children and their families; and A. Hart, T. Nishida,
A. Pinkham, J. van Reet, and B. Rosen.
Supporting Online Material
Mean z score
Sophisticated sentence structures
Creative story
Positive social strategies
Sense of school as community
Results for 12-year-olds.
Students in the Montessori pro-
gram wrote more sophisticated
and creative stories and showed
a more developed sense of com-
munity and social skills. Scores
were converted to average
z scores (18).
Published by AAAS
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... Actual studies in conventional schools also show that features consistent with Montessori (like low test anxiety: Montessori has no tests) predict higher wellbeing in school (Baker, 2004;Cohen, 2006;Felner et al., 2007;Steinmayr et al., 2016Steinmayr et al., , 2018. Furthermore, random lottery studies of Montessori students (discussed later) show differences from waitlisted controls suggesting Montessori lays groundwork that would be expected to lead to higher wellbeing (Lillard and Else-Quest, 2006;Lillard et al., 2017). Here we present a series of structural equation models showing that Montessori schooling in childhood is associated with higher adult wellbeing, after accounting for a range of demographic variables. ...
... This makes sense because, as opposed to conventional schools where students usually work individually, in Montessori schools students often work in small groups. Moreover, research indicates that Montessori student's social knowledge and skills are more advanced, and the overall school climate is better (Flynn, 1991;Rathunde and Csikszentmihalyi, 2005b;Lillard and Else-Quest, 2006;Lillard et al., 2017;Denervaud et al., 2020a). Random lottery studies also indicate that academic performance is stronger in Montessori (Lillard and Else-Quest, 2006;Lillard et al., 2017) and well-controlled matched/growth studies (e.g., Culclasure et al., 2018;Denervaud et al., 2019) suggest Montessori leads to higher academic performance. ...
... The studies thus have high internal validity, although the results might not apply to families that do not enter such lotteries, lowering external validity. The first study examined children in Kindergarten and 6th grade (Lillard and Else-Quest, 2006), whereas the second followed across preschool (from ages 3 to 6) children who were equal on all measured outcomes at baseline . Both contrasted children in high fidelity public Montessori schools (in that both met the standards for recognition by the Association Montessori Internationale or AMI, which meant all the teachers had AMI's intensive 9-month training and diploma) with waitlist control children in business-as-usual non-Montessori schools. ...
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In recent years, the school curricula in many European countries have introduced social and emotional learning (SEL). This calls for the teachers to have SEL competencies. The present study evaluates teachers’ and their students’ readiness for SEL during an intervention in five European countries. The participants were teachers (n = 402) in five European countries; Italy, Latvia, Lithuania, Slovenia, and Spain. The pre-and post-measuring points for both the intervention and the comparison group were at approximately the same time before and after the intervention. Comparison data consisted of 159 teachers in the same countries. The training for the intervention group lasted 16 h for the teachers and a maximum of 16 h for the principles and headmasters. An additional 9 h of further monitoring took place. There were two student groups participating in the study: the age group of 8–11 years (pre-puberty) and the age group of 12–15 years (adolescents). Students, whose teachers had participated in the intervention, formed the intervention group (n = 2,552). Those students, whose teachers did not participate in the intervention, formed the comparison group (n = 1,730). The questionnaire data were collected at the beginning and at the end of the school year for both age groups. The results indicated that there was a favourable development in the intervention group in some of the measured skills among students, but the effects were different for the two age groups. This study adds to both theoretical and practical development of continuing teacher training about SEL and its possible role in reducing problem behaviour among the students.
... Although limited in number, several studies have evaluated the relationship between Montessori and creativity (Lepper, Greene, and Nisbett, 1973;Amabile & Gitomer, 1984;Ryan & Grolnick, 1986;Amabile, Hennessey, & Grossman, 1986;Lillard and Else-Quest, 2006;Byron and Khazanchi, 2012;Cossentino and Brown, 2016;Lillard et al., 2017). Most studies, but not all, have found a positive relationship between Montessori and creative development. ...
... If not accounted for, the higher levels of creativity exhibited by Montessori students on the final EPoC score may be simply due to the fact that they have more involved parents and not because of their participation in Montessori education. Unlike some other studies that have examined the effects of Montessori education Lillard & Else-Quest, 2006), this evaluation was not able to use a randomized lottery to account for selection bias. Rather, researchers hoped to lessen selection bias by selecting a school district that only ...
... From the age of 6 years, explorative learning is enhanced using all the knowledge acquired through exploration and experience by collaborating with other classmates which is key for the effectiveness of divergent thinking. This environment has been shown to favor creative thinking (Besançon & Lubart, 2007;Lillard & Else-Quest, 2006), independently of cognitive control and fluid intelligence abilities (Denervaud et al., 2019). Therefore, investigating both divergent and convergent thinking in different school settings might shed new lights on our understanding of the development of creative thinking. ...
Creative thinking is critical to overcome many daily life situations. As such, there has been a growing interest on how creative thinking develops during childhood. However, little is known about the underlying mechanisms driving its development. Indeed, almost all research has focused on divergent thinking, leaving aside convergent thinking, and did not thoroughly investigate how internal and/or external factors influence their development. Here, 222 children aged from 4 to 12 years old attending either a Montessori or a traditional school performed drawing‐based convergent and divergent standardized tasks. In addition, a subset of 41 children were tested using similar tasks for a second session 3 years apart. The results revealed dynamic developmental stages of convergent and divergent thinking. More specifically, a loss of divergent thinking was counterbalanced by a gain of convergent thinking, especially during the fourth‐grade slump (8–10 years old). Although Montessori‐schooled children showed overall higher creative abilities than traditionally schooled children, no differences were observed in the developmental trajectories of convergent and divergent thinking between the two pedagogies. This suggests that progress and decrease in creative thinking may be mostly due to internal factors such as brain maturation factors than external factors such as peer pressure.
... The North American Montessori Teachers' Association (n.d.) estimates that there are approximately 4,500 Montessori schools in the United States and 20,000 worldwide. Montessori education is mainly known for its attention to multiage classrooms, Montessori-specific educational materials, student-centered approach, independent emphasis, uninterrupted work time, guided-choice of work activities, collaboration, and teacher training (Lillard & Else-Quest, 2006). A significant feature of Montessori education is that it is designed for teachers to spend a significant amount of oneon-one time with students to respond to each child's interests and needs, thereby allowing them to learn at their own pace and level (Lillard, 2008). ...
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... The North American Montessori Teachers' Association (n.d.) estimates that there are approximately 4,500 Montessori schools in the United States and 20,000 worldwide. Montessori education is mainly known for its attention to: multiage classrooms, Montessori-specific educational materials, student-centered approach, independent emphasis, uninterrupted work time, guidedchoice of work activities, collaboration, and teacher training (Lillard & Else-Quest, 2006). A significant difference between Montessori and traditional education is Montessori's focus on each child's interests and needs, thereby allowing each child to learn at their own pace and level (Lillard, 2008). ...
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