Assessment in PBL

Previously I’ve written about problem based learning (PBL), and I did just finished another round with the heat problem in Physics 11. A couple of issues have been revealed this year, and I’m not entirely sure what to do about them. The first issue is one of differentiation. This year I’ve had three classes try out the problem. All three had 2 full periods to solve the problem, but very few groups actually finished the problem to the state where a solution was written up or sample calculations were done.