A 2 x 2 factorial design was used to investigate the effect on teaching competencies (measured by applying the Instrument for the Analysis of Science Teaching, the Classroom Observation Rating Form, and the Teacher Performance Competencies Scale to videotapes of subjects teaching in one-to-one or one-to-two situations), and attitudes (measured by a semantic differential) toward a number of aspects of teaching practice and theory. The student teachers taught microlessons to elementary school pupils or to their peers in the science methods class. The other variable was presence or absence of feedback from an experienced teacher. Students who taught peers developed competencies and attitudes similar to those of students who taught children, although some pacing skills and questioning techniques were only developed by those teaching children. Systematic feedback from experienced teachers was necessary for the improvement of lesson pacing and clarity of presentation. There were few differences in attitudes between the groups with or without feedback. (AL)