My Girl Scout troop is going to be starting their science badge next week. One of the things we will explore is density. We are going to do a "Will it Float?" tank using mostly fruits. I was thinking that it would be fun to bring in two eggs, one fresh that would sink and the other not so fresh that would float... to see if we can get the girls thinking. The problem: I don't have any old eggs. Is there a way I can force and egg to age enough that it will float in 5 days???