For invitations, I wrote a poem giving the type, time, place, who it was for, and since I used the computer, could personalize it by placing the child's first name in his/her invitation. We set up a slip 'n slide, small wading pool (a 5 year old's party) a fancy sprinkler and a nylon "house" that holds about 4 at a time. The garage was totally cleaned out except for the Vegetable items from Birthday Express. The party was a big hit. We had done the exact same thing last year with a Powerpuff Girl theme and kids started asking me in May if we were going to do it again. I even got a report from one Mom saying that her son cried and cried because his vacation to the beach meant he couldn't come to the party this year. I didn't call it a "party" but a birthday splash. It is amazing, I watch some parents spend real big bucks for entertainment when its  simple stuff like playing in water that has the most appeal......and it seemed like everyone remembered the 1st. party  which lead to a lot of excitement over the 2nd.!!!