This was a craft idea with my son's school curriculum. Oh it is too cute! You get a black balloon. Out of poster board cut feet (together), flippers, beak and a white belly. I had my kids paint the feet and beak orange and flippers black, but you could just buy those colors. Use googly eyes or cut eyes out of poster board too. Make a slit in the feet halfway through. Slide the knotted end of the balloon through. Tape or glue on the rest of the penguin.
Disclaimer: Our balloons did pop when the kids pulled on the flippers that were taped on, little disappointing for the 2 year old.