Can you get online and watch some episodes of Play School? Seriously, I would have no idea how to make a cereal box anything other than a cereal box if it weren't for that show! LOL I am creatively challenged like that. Ceebeebies would have some similar things on it too that you might get some direction from. Art Attack is awesome too.

There is that dough footprint recipe too, he could press his dinosaurs or something into it and bake and paint to hang on his wall.

Do you have any hands-on science museums near you (we have ScienceWorks here which a whole range of age-appropriate activities they can do and participate in, whole days have known to be consumed with ScienceWorks! LOL)