Well for my daughter's 6th birthday party we had a blast and so did the kids!!! We had 32 kids come to the party and there was loads of fun for every child. Start off by making up water games for the kids to play. Ex. we played water kick ball and water baseball loads of fun!! Then we went on to have water balloon fights and water gun fights!!!! I would have to say that the shaving cream war was the funnest grown ups and kids played it was loads of fun. After we played all of the games the kids played in two big above ground pools 18ft by 4ft. We also had a big water slide that had a rock wall up the back and had 2 slides down the front 12ft tall. The kids loved it!! The next thing we did was have a hula dance contest and it was loads of fun to watch the kids show off their dance moves. While all of this was going on we were serving pickles, snow cones, nachos, sausage on a stick. Then we had cake and ice cream and presents.  The kids dressed in bath suits. Hula skirts & cococunt tops were given for girls and flower mesh shorts for the boys with sunglasses. It was the cheapest party my husband and I have given our daughter so for and it was the funnest and had the most to do. Cost with having water slide or underground pool or above ground pool $175-$200. Party could cost more if need to buy water slide or a pool. This includes everything food and toys and clothes given to each child. I used alot of neon colors and flowers and flamingo's to decorate the party with large parrrots as well.  Had a over sized flamingo for all of the kids to sign their names for my daughter's keep sake.  That is the sum of my daughter's party. Thank you so much for reading my idea. Brandy