How do you do the soda experiment on eggs?

First you need to hard boil as many eggs you need for the experiment. Then pour soda into cups; use both dark and light colored sodas so you can compare/contrast the effects of different colored sodas on your teeth. Put the hard-boiled eggs into the cups (one egg per cup) making sure that the egg is completely covered with soda. Allow the egg to sit overnight. The next day, remove the eggs from the soda cups. Discuss how the eggs are stained because of the soda which is why we must brush our teeth to keep them from being stained. I like to follow up with a lesson about brushing with fluoride toothpaste afterwards and have my students "brush" the egg clean.