Setting
The study took place in 10 schools in Montgomery County Public Schools, a large, suburban
school district in Maryland. The study population has no ethnic majority and is among the
highest performing in Maryland.
Study sample
In this randomized study, researchers created a sampling frame consisting of five profile
categories, with approximately seven schools in each category. Each school category has a
similar demographic and achievement profile determined by percentage of students eligible for
free and reduced-price meals, math and reading achievement scores, ethnicity, eligibility for
English for Speakers of Other Languages (ESOL) services, and eligibility for special education
services. Two schools were randomly selected from each category to participate in the study.
In each category, one school of the matched pair was then randomly chosen to implement the
intervention and the other was the comparison school. The study school sample consisted of
five schools implementing the intervention and five schools not implementing it. The analysis
is based on two cohorts of eighth-grade students that attended the study schools during two
consecutive school years. Cohort 1 was formed in the 2001–02 school year and consisted
of 1,087 eighth-grade students who received Chemistry That Applies in the five intervention
schools and 809 eighth-grade students in the five comparison schools who received a regular
science curriculum. Cohort 2 was formed in the 2002–03 school year in the same schools
and consisted of 1,121 eighth-grade students who received Chemistry That Applies in the
five intervention schools and 1,159 eighth-grade students in the five comparison schools who
received a regular science curriculum. Differential attrition rate of students was low for Cohort 2
(3%) and high for Cohort 1 (13%). Because of the high attrition in Cohort 1, the WWC confirmed
that baseline equivalence for Cohort 1 intervention and comparison groups was demonstrated.
The study reported student outcomes for the two cohorts after seven weeks of program implementation; these findings can be found in Appendix C. Additional findings for subgroups by
gender, race/ethnicity, students in the Free and Reduced Price Lunch (FRPL) program, those in
the ESOL program, and those eligible for Special Education (SPED) can be found in Appendix D.
Intervention Group
The curriculum unit employed by the experimental group was Chemistry That Applies (State
of Michigan, 1993). Chemistry That Applies is a middle school science curriculum that received
an acceptable rating by Project 2061, a curriculum analysis project funded by the Interagency
Educational Research Initiative of the National Science Foundation (NSF). Chemistry That
Applies consists of 24 lessons. In this study, teachers were instructed to cover the first 18 lessons
only because the topics covered in the last six lessons were not part of the district curriculum
and hence not covered in the comparison group. Chemistry That Applies focuses on “guided
inquiry” with hands-on, student-centered material. Working in large and small groups, students
explore chemical reactions, collect data, and use evidence-based arguments to support their
claims. Students keep individual science notebooks for analyzing results. Chemistry That
Applies provides question prompts (called “Think and Write”) that require students to use
critical thinking skills. Complicated vocabulary is kept to a minimum. The unit is implemented
over a period of approximately seven weeks.
Comparison Group
Comparison group teachers used regular curriculum materials normally available to Montgomery
County Public Schools teachers that addressed the same target benchmarks. The comparison
group curriculum comes from a range of sources, including traditional textbooks, Prentice Hall,
reform-based NSF-funded materials, and teacher-designed materials. All teachers were exposed
to professional development and “reform-based” strategies.
Outcome descriptions
For both the pretest and the posttest, students took the Conservation of Matter Assessment
(COMA). For a more detailed description of this outcome measure, see Appendix B.
Support for implementation
All intervention group eighth-grade science teachers participated in two days of professional
development. They also were given a box of lab materials, instructions for implementation,
and an unspecified number of follow-up meetings during the school year. All teachers had
access to their regular professional development meetings.