An investigation into the effects of completion problems on the performance of introductory physics students
In this study the completion problems were voluntary. I believe it has been reasonably shown that the completion problems do not have a negative effect on test performance. If the act of completing a completion problem is useful making the completion problems mandatory would seem to be a simple improvement that may result in further or more widespread gains. Further, I believe that completion problems are realistic to implement for an entire semester or year-long course, in terms of time invested in creation of the problems compared to the possible gains made by students. The study has also shown that completion problems can be implemented without significantly altering the rest of the course (i.e. lectures, exams and tutorials).