well if you are having 26 people in your back yard, im gonna assume its pretty big. At my partys i usually have it in my shed/backyard. What i do is rent a movie (anything popular at that time), play it in the shed. Outside i have a volleyball net and a basketball goal. So some people just goof around and play. I always have a bunch of food, and music goin to...i know it doesnt have a fancy theme or anyhing, but we always have fun just hangin out. Plus, themes are usually to much hassle and people feel to much presure. THis way it is low key and everyone is comfortable. If you have a trampoline or something like that it is fun too.