Reports on a study that investigated the effects of various instructional practices on programming proficiency focusing on characteristics of Pascal classes. States that instructional practices involve extensive on-line access, explicit instruction, and extensive feedback. (ML)

Uses two studies to examine developmental and task effects in estimation problems. Results are discussed in terms of student and task characteristics and the implications of such variables on information processing model of learning. Implications for science teaching, learning problem diagnostics, and science curricula are also discussed. (TW)