The Egg Drop

Me and my brother havent been able to spend much time together, so I thought this was a good oppurtunity to do something together.

He has a project for school, and he's really excited about it. He told me (dont remember all the details) that he is building a small container, so that when he drops an egg (while in the container) from various heights, it wont break.

He plans on putting things inside the container to keep the egg from breaking. I gave him the common sense info, like stuffing it with cotton balls.

Do you guys have any other ideas to help my little brother out? Like what to stuff it with? What type of materials to build the container out of?