What should my friend have to do as a consquence for loosing a bet?

My friend and I made a bet and she lost and we r tryin to think of somethin really good to make her do, but we don't want it to be streakin or have to do anything with wearing anything, we also don't want it to be gross we want it to be funny for the both of us do u have any suggestions...btw we r in high school so it cant be like drinkin or anythin illegal for us...please give suggestions they will be mucho appreciated.