Let's Play by Herve Tullet. Let's see -- a big yellow pom pom and a piece of string? They really liked this, it was so interactive. We did it without the pom pom, and even the runners got involved.
White Rabbits Shape Book by Alan Baker. Couldn't find the book but I had taped the whole thing onto the lid of the BIG SQUARE GREEN BOX. The babies love this -- taking out the white cylinder, blowing up the round balloons, letting them go and spiral around wildly in the air. A big show.
Ticklemonster by Manceau.
Shape by Shape by Suse MacDonald. A bit like Big Green Monster, i.e., aDORable. But don't forget to hide the cover!!! And don't forget the intro: this is a guessing game, and it's being read by the brachiosaurus, so be a brachiosaurus!
Mouse Shapes by Ellen Stoll Walsh. A flannelboard must.