Ideas for backyard fun birthday party?

Also check the Family Fun magazine's website. We did the carnival theme for my son's fifth birthday and it was a blast. We made a home made ticket booth out of a refrigerator box. We hired a teenage neighbor girl to come do face painting. That was a big hit for the kids and really easy. We had the moonwalk/bounce thing in the backyard, but we also threw in some old classics like sack races and musical chairs. I kept the food simple, like hotdogs, popcorn and cupcakes. We also made a homemade picture board. We had a big piece of old plywood and made a frame for it so it woud stand up. We painted a clown on it and had a hole cut out where his face would be. The kids loved getting their pics taken there. I used the pictures in the thank you notes when we sent them out. On the picture board, you could probably use canvas fabric and paint on that. It would be easy to hang up for pictures.

Sounds great, Im having a carnival party for my son with the same stuff your having, check the Parents Magazine website and in the search box type Carnival they have really cute inexpensive ideas for backyard fun

try helium baloons, sports ie. baseball depending on the size of back yard, babmitten or volleyball, small kids pool! good barbecue hamburgers, hot dogs or bacon wraped in hot dogs!