Recent studies have documented a decline in academic performance and motivation as students move from elementary to middle level schools. This paper expands these studies in three ways: (1) by examining the classroom-level differences among middle school students' motivation to see if motivational constructs vary by classroom; (2) by exploring the specific within-classroom factors that affect early adolescents' motivation in mathematics and science; and (3) by using Hierarchical Linear Modeling (HLM) which is a multilevel technique. The 673 students in the study came from two middle schools in a largely blue collar community--most of the students were white. Participants completed the Patterns of Adaptive Learning Survey as well as questionnaires pertaining to specific academic subjects. All teachers filled out questionnaires assessing their pedagogical beliefs, instructional practices, and perceptions of the school culture. Results indicate that math teachers had a significant effect on their students' self-concept of ability. Likewise, science teachers who used ability-focused instructional practices, had students with lower measures of "learning focus" toward science than teachers who did not publicly acknowledge test scores or grades. Similar investigations are advocated for the later middle school and high school levels. Eight tables provide statistical summaries. (RJM)