My idea is for a Capture the Flag party. I'm going to be turning 14 so I thought, I'll try something new. Our local park district has a lot of hiking trails and camp outs areas around it so it'll take place there. The invitations could be a torn up piece of paper with all the usuals on it. Then also send with it a colored bandana (i.e. a orange bandana for the orange team). Then once all the guests get there, with they're bandanas showing what team they are on. (there are 2 teams) Each team has a headquarters where the flag is located. You'll also need lots of water balloons, it should also be hot out. (you might need to explain the game to your guests)  Some people stay back an guard the flag while others head out to get the other teams flag is. The point of the game is to capture the other team's flag and bring it back to your team headquarters. You can also capture prisoners from the other team and put them in the jail at the headquarters. If you hit them with a water balloon, then you've caught them. But you have to keep your jail guarded, or all the prisoners can run away. No hitting or tackling is allowed for the player's safety. During the duration of the game you should have water, in case anybody is thirsty. When it's over, everybody comes back from food, and a small party. (i.e. time for cake, presents, music and all that stuff) have fun! and play safe!