In problem-based learning, an instrument is needed to measure students' actual learning activities. Mapping the domain of learning activities undertaken by students and improving problems is especially important in a problem-based curriculum because students choose their own learning objectives. Such an instrument, the Topic Evaluation Questionnaire (TEQ), was developed. The TEQ's reliability and validity were assessed, as well as its usefulness as an indicator of problem areas in a course's content. Subjects were 125 second-year students attending the Medical School of the University of Limburg (Netherlands) enrolled in a childbirth and child development course. The TEQ contains 134 topics from the course and eight topics indirectly related but included to estimate response set effects. For each topic, a Likert-type question was formulated to measure student perceptions of time they had spent studying the topic. Students were also administered a 222-item true/false type achievement test on the course material. In all, 210 achievement test items were classified by a teacher and an independent rater. The TEQ appeared to be reliable and was fairly valid. It appeared to be useful in measuring problem areas in course content, as well as student's actual learning activities. In sum, the T.E.Q. informs as to whether the goals set by teachers are reached by students. One table and one bar graph are provided. (SLD)