Thanks a lot, everyone. His projects were Astronomy, It's about time, which involved building a pendulum from scratch and Physics Lab, building a wind turbine to study energy conversion. They were all assigned the subjects, and prepared the models. They were initially judged by the creativity of their project and then had to take a written test on the subject. 2 questions, no multiple choice but actaully written ones.
I really appreciate all your nice comments.
Thanks.