Developing and Testing a Model to Support Student Understanding of the Sub-Microscopic Interactions that Govern Biological and Chemical Processes

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This project designs, develops, and tests coherent interdisciplinary instructional materials to support high school students' integrated understanding of the forces and energetics involved in interactions that occur between atoms and molecules, and explores how students' learning progresses across time. Instructional materials focus on physical science core ideas identified in "A Framework for K-12 Science Education" (NRC, 2011), and "College Board Standards for College Success" (College Board, 2009). The two research questions are: (1) How does learning progress over time when students experience a set of interdisciplinary instructional materials designed to help them advance toward important learning goals related to interactions at very small scales?; and (2) How do the various learning activities support the development of integrated understanding? The project is implemented in three Michigan school districts with students who traditionally do not succeed in science. Two of the school districts serve urban communities with ethnically diverse student populations; the third serves a rural, primarily Caucasian community. To develop and test instructional materials and associated assessments, the project joins efforts with the Concord Consortium and employs the Construct-Centered Design process (a principled process based on evidence-centered assessment and learning goal-driven designs); uses physical and computer-based models and simulations; and draws on previous and ongoing work on a learning progression of the hypothetical students' path in their understanding of the structure, properties, interactions, and transformations of matter. Four instructional units are produced: (1) Introduction to Electrical Forces, (2) Water, (3) Larger Molecules, and (4) Bio-Molecules, with a duration of two to six weeks each. After testing for usability, the units go through two additional phases. Phase I comprises pilot testing with at least one teacher at two sites, two classrooms each, yielding information from 100-120 students per unit. Phase II consists of field testing the units with a larger sample. Using a power analysis to determine sample size, the project tests two different sequences of the units: (a) four teachers, eight classrooms, and 200 students use the units as a single semester course before taking biology or chemistry; and (b) four teachers, eight classrooms, and 200 students use the units in appropriate points within a chemistry or biology course. Eight teachers from the same school districts, 16 classrooms, and 400 students who do not use the units, serve as the comparison group. A mixed-methods approach is used to collect and analyze data. Data collection strategies include: (a) pre- and post- tests, (b) unit-embedded assessments, (c) students' interest and attitudes, (d) assessments to place students in the learning progression, (e) classroom observations, (f) analysis of student classroom work, and (g) interviews with students and teachers. Data interpretation strategies include: (a) coding of students' and teachers' responses from interviews, (b) identification of patterns, and (c) using item-response theory (IRT) procedures to place students' responses in the learning progression. A range of methods are used to assess validity and reliability of instruments used, including: (a) construct validity, (b) content validity, and (c) IRT procedures. Project external evaluation addresses both formative and summative aspects. Key project outcomes include: (a) a research-informed and field-tested semester-long course comprising four integrated units with specific objectives, learning tasks, phenomena to illustrate and support understanding at key points, reading materials, and embedded assessments; (b) computer simulations aligned with the units; (c) educative materials for teachers; (d) valid and reliable instruments to measure students' understanding and attitudes; and (e) a set of research manuscripts focused on how the new materials work and promote student learning of key challenging ideas.