Findings about student achievement, question 1: what is the impact of the MiC instructional approach on student achievement?

The data used to answer this question are based on 17 separate studies: eight grade-level-by-year studies, six cross-sectional studies, and three longitudinal studies (see Figure 2.1 in Chapter 2). In this chapter, the findings are first reported by teacher/student groups in the grade-level-by-year studies. (A teacher/student group consists of students in one or more classes taught by the same teacher.) Second, because the teacher/student groups are nested within districts, the findings for the four districts are used to examine the cross-grade and cross-year studies. Finally, because most students did not stay in the same teacher/student group for more than one year, individual student scores are used in the longitudinal studies (Romberg, Shafer, Webb, & Folgert, 2005b).