Energy transfer

With my class 6 students I have been working on energy and energy transfer. After learning the theory, the different types of energy and the principle that that energy can not be lost only transferred; it was time to put theory to practice.
Students were asked to investigate the transfer of strain energy to kinetic energy by means of a catapult. Last week the looked at the research question, hypothesis and how they could design an experiment to test the hypothesis. Today it was time to put design into practice!