This set of stacking baby blocks is adorable, and has proved to be a huge hit in my household.Each block has a cute animal head on top, three fun sides (plus a side that doesn't do anything) and a concave bottom that allows the blocks to stack.The activities include a butterfly that “flaps†a wing from side to side, revealing bright illustrations with A, B, C and 1, 2, 3; a clicking spinning wheel; a sliding barn door; an illustration of a cat; a mirror; a clicking spinning dog bone; two sliding shapes; and a textured panel.Because the animal heads fit nicely into the concave bottoms of the next block, these blocks tower together very nicely in a way that allows baby success as they don't fall off each other easily.My overall impression with these blocks is that they are really cute, and are very attractive to young children. That said, at $20 for three blocks, I feel that they are overpriced, especially given that they each have a side that doesn't do anything.