guess what? if you give a 5 yr old and a 6 yr old the blue mouthwash for kids(really cool-- it sort of temporarily stains the plaque, showing them where to brush more! you do this before they brush), and you put them in front of a couple of white sinks. Then you turn your back for a sec to check the 8 yr old's question. When you look back you will see two kids grinning all smurfy blue and the sinks will look like you ran the blue stuff through a sprinkler in your bathroom. I am trying to figure out if they actually learned anything. I did.