This study answers two research questions: (1) How do 12- and 13-year-old students respond to metacognitive questions posed during a complex task in mathematics or in science and (2) Do these responses differ by discipline? Content analysis was applied to responses collected from 92 students from a French-speaking Belgian school. The results showed that students are able to respond to metacognitive questions. However, the responses were not clear and were simplistic when they talked about their strategies. The difficulties students faced in developing their responses were identical in both disciplines.