The UNO H2O card game created by Mattel is a fantastic idea that should have been "invented" years ago!
Mattel has taken the classic game of UNO and simply made the card out of thin clear plastic instead of traditional paper card material.
My son's been playing UNO since about age 4, so I think the age suggestion of 7-99 is a little off base, but use your own judgement when playing with little ones.
The beauty of these new clear plastic UNO cards is that they are totally waterproof! We've taken these to the pool multiple times and the kids can all play with them, even if they are soaking wet. They are also "milk-proof" which we found out the hard way when we had a little milk spill as we were playing. They were slightly sticky, but I was able to clean the cards and the deck is like new. With traditional playing cards, the game would have been destroyed during the milk incident.
I really love card games, and UNO is one of my all time favorites. I recommend UNO H2O for all families!