Clothespins are awesome, a lot of creative crafts can be done with them, and the best of it that they are really cheap, you can get 50 of them at a dollar. In case you're short of ideas about what can be done with clothespins, we have a nice compilation here for you of the most interesting and fun projects for you and your kids.
Shape Monsters - We read Glad Monster/Sad Monster with this activity, and made different types of mouths/eyes. The kids really loved their finished product. It took quite a bit longer than I had originally planned. Might be better to do with just 1 or 2 kids during center time instead of a larger group of kids.