The AP Biology students went to the library and participated in a Virtual Fly Lab experience. They ordered flies, mated them, made them unconscious, counted them, mated them again, counted them again, analyzed results. Yeah, a bunch of stuff.
The Chemistry students did a bunch of practice balancing equations problems. Balancing equations is a lot like riding a bike. You practice and practice. You get hit by a car now and then. You fall and break your wrist down by Ol' Man Clements house. You eventually get good enough to enter a bike riding race where you tragically fall off the bike during the sprint phase of the race and get run over by a truck load of race photographers. Just like balancing equations.