Academic performance appears to be influenced by the combined effects of at least seven important variables: 1) inherited capacity to learn, 2) learning experiences, 3) external resources, 4) attitude toward teachers, 5) perceptions of teacher expectations and values, 6) perceptions of the future utility of schooling, and 7) self-concept of ability. While there seems little need to measure the first variable because it cannot be altered and the next two must be measured in relation to the unique goals of particular schools, the other four variables can be assessed using a broadly applicable instrument, the Student Achievement Diagnostic Questionnaire (SADQ). The SADQ allows student perceptions of teachers, schooling, and themselves to be measured and compared by school, grade level, and discipline, revealing strengths and weaknesses in individual programs. Basic strategies for improving student perceptions in areas where they are negative can then be applied by individual teachers in order to enhance students' academic performance. (Author/PGD)