With the widening knowledge base students will need to be more flexible in their learning habits. Traditionally, teaching school science often involves teacher-centred methods like lectures, experimental demonstration or guided inquiry. Plain knowledge dissemination will not adequately prepare students to cope with the changing world. Hence, schools need to train students to be reflective in their learning habits--that is, getting students to be observant, to generate relevant alternatives and to make sense of these ideas. This article discusses a well-documented reflective learning strategy--the use of "what if" questions, to help students extend their learning beyond curricular requirements. Students are introduced to a distillation set up and then asked to pose "what if" questions about it. Their questions and the corresponding peer responses are a wealth of information for teachers to explore how science may be taught differently and with a greater impact on their students' learning experience. (Contains 3 tables and 2 figures.)