Evidence of gains in student understanding of science through the use of GEMS.
The study involved the application of Nussbaums Earth Notions
Classification Scheme to results of testing of 159 boys and girls from
public schools in San Francisco, and the relation of these results to
research conducted in Nepal, Israel, and Ithaca, New York. The classification
scheme was itself subjected to rigorous analysis (see under "Results/Validation
and Refinement of the Earth Notions Classification Scheme, page 211217)
with statistical and prediction analysis, resulting in a suggested refinement
to include an additional notion between Notions III and IV in Nussbaums
classification. Results were analyzed based on age and grade, and in
relation to previous research, and confirmed that children interpret
information about the spherical Earth and gravity in terms of their
own models of the world, and that these interpretations, while representing
reasonable "alternative frameworks" from the childs
point of view, require considerable additional learning experience to
be transformed into accurate scientific conceptions.
Since the GEMS unit was developed, tested, and published, additional studies have evaluated the extent to which the activities in the unit succeed in overcoming student misconceptions. "Unraveling Students Misconceptions about the Earths Shape and Gravity," details a study involving 539 students from 18 classrooms in 10 different states. The experimental treatment was the GEMS unit, Earth, Moon, and Stars. The primary experiment was a treatment-group-only design, in which teachers (trained in the use of the questionnaire assessment instrument at a summer institute sponsored by NSF) administered the same test to all students before and after the treatment. The purpose was to determine the impact of the treatment on students understanding of the Earths shape and gravity concepts. Data were analyzed in three age groups (4th and 5th graders; sixth graders; and 7th and 8th graders). As expected from previous studies, on the pretest all classes displayed a wide variety of conceptions about these concepts. After the unit, however, the number of subjects who held misconceptions was far fewer. Chi-square analyses showed that a significant number of students at all grade levels shed their misconceptions concerning both the Earths shape and gravity. A surprising finding was that younger subjects responded more positively to the experimental treatment than older students, so that, after instruction in the GEMS unit, fourth and fifth graders were as knowledgeable as seventh and eighth graders concerning the Earths shape and gravity. While the GEMS unit was tested and found effective from Grades 48, the study suggests that this may indicate that presentation of the unit at the earlier grade levels may be particularly beneficial.
As Table 4 on page 279 of the Sneider Ohadi article depicts, percentages
of students who demonstrated increased understanding of the Earths
shape before and after the GEMS unit went from 24% to 72% for Grades
45; from 27% to 45% for Grade 6; and from 38% to 62% for Grades
78. The percentage of students understanding gravity went from
7% to 67% for Grades 45; from 15% to 47% for Grade 6; and from
30% to 60% for Grades 78. In conclusion, the authors state: "
concepts selected for study by the studentsthe earths spherical
shape and gravitywere considered by many researchers to be of
fundamental importance in allowing students to understand the modern
scientific explanations of a wide variety of phenomena, such as the
daily cycle of the sun, phases of the moon, and seasons. These findings
were bolstered by a full-experimental, control-group study
the conclusion that the constructivist teaching unitEarth,
Moon, and Stars, from the GEMS seriesenabled large numbers
of students to unravel their misconceptions and construct a more accurate
model of the world." (Emphasis added.) These studies, and additional
studies and articles referenced below, have also had a significant impact
on further curriculum development in GEMS, in particular on the Moons
of Jupiter and Messages from Space units (see Sneider articles
in collaboration with Varda Bar and others cited below on gravity in
space, weight and free fall, and gravity and air). As the Sneider Ohadi
study progressed, insights gained were taken into account as the GEMS
assessment handbook was developed and as revisions of Earth, Moon,
and Stars were published.
The Galaxy Classroom Project (Pilot Program 1991-1995) funded by Hughes Aircraft and the National Science Foundation: The Galaxy Classroom Project is a multimedia, year-long program for K5 students in classrooms nationwide. A main goal of the K2 component is to impact student learning of the science/mathematics concepts and processes of observing, comparing, communicating, properties of solids and liquids, structure/function of living organisms. The Pilot Program consisted of a core classroom curriculum from the GEMS and FOSS projects of LHS with two series of interactive television programs designed to incorporate the science and math concepts emphasized in the classroom program. Family home activities and classroom activities involving fax and the Internet are also included. The program is currently being conducted statewide in Georgia, in selected districts in California, elsewhere in the United States, and in Canada. Since 1995, the Project revised their classroom curriculum to include only GEMS units. The GEMS units for the K2 program include Terrarium Habitats, Liquid Explorations, and other GEMS early childhood units. The 3rd through 5th grade program focuses on Bubble-ology, Oobleck, Chemical Reactions, Investigating Artifacts, and five others. As is typical of GEMS, several of these units also have a strong mathematics component. The executive summary of the final report of the Galaxy K2 program show student gains in learning key concepts, improvements in teacher instructional practices, and an increase in curiosity of students. The evaluation gathered quantitative data on GALAXYS impact on student learning through pre-post tests of observation skills and an assessment of the science content presented. The report also states: "Teacher reports and evaluation results confirm that most students understood the concepts of the two GALAXY themes (recognizing and comparing the properties of various liquids, solids, and mixtures and identifying and comparing the characteristics and features of insects)." The report adds, "GALAXY first and second graders exhibited a striking and statistically significant growth in curiosity when compared to their non-GALAXY peers." (Page1, Far West Laboratory, Final Report.) The Far West Laboratory for Educational Research and Development (currently West Ed Laboratory) of San Francisco conducted the evaluation for the Galaxy Classroom Project. It was directed by Dr. Gloria Guth.
Childrens understanding and retention of some of the content
taught was measured by how well they could identify six animals presented
in the units and by evaluating their responses to questions about the
diet, habitats, and defense behaviors of those animals. Students were
first given a dichotomous score (correct/incorrect) for their knowledge
of the identity and behaviors of these six animals. The findings indicate
that children exposed to the curriculum did, in fact, learn and retain
content about the behaviors of the animals they are studying.
Critical value of t at 17df = 2.110, p< .05*; 2.898, p< .01**; 3.965, p< .001***
Critical value of t at 3df = 3.182, p< .05*
Note: The accuracy of teachers perceptions that children
became more sophisticated in some of their cognitive skills because
of the PEACHES/GEMS units was also evaluated. While sufficient evidence
was not found for this, the great majority of teachers reported that
their students became better reasoners after they experienced
the PEACHES/GEMS units, so this may merit further study. Insufficient
evidence was also found for another teachers reportthat
the units had a positive impact on sorting and classification skills.
Again, a longer-term study might reveal qualitative gains in classification
skills that were not demonstrated in this short-term evaluation.