T.R.
OHHH there are so many!!!!! I used to not know of any and I made it my mission to find a bunch.... I will say that Common wealth lake has two.. very nice and clean ones... one across the street and another on the other side of the lake... tons of ducks and a great walk around.
There is beaverton park that has the foutians.. that is fun on a hot day.
I have a site that I will be putting up a bunch of places... Give me about two weeks to get jump started.. Been a bit busy... I hope to get one up tonight or tomorrow... http://thingsandplacesforkids.blogspot.com/
It has a bunch of other fun stuff on there.. spread the word if you like it... Good luck dear.. I will do my best to get a few up there!