I have the best husband with whom to co-host birthday parties for children. Give him an idea (say, an Olympics theme) and the next thing you know odds and ends from the garage, basement and attic appear in the back yard, arranged into an obstacle course, or high jump (with bouncy landing pad), or relay track.
This was a three hour party. At least two hours were spent on the Olympic events in the back yard. For a full hour, kid you not, the mostly-seven-year-old crowd lined up and took turns jumping over a pool noodle onto a mattress to great cheers and applause.