Hey! Okay for my 11th b-day me and my friends had a blast! I had about 10-15 girls come over and we all ate pizza and opened presents. Then we split up into 2 teams and had a scavenger hunt. It was a blast! After we were done with that we came back to my house and had cake and ice cream. You and your friends can have fun dancing and listening to music. Watch movies and just hang out. It can be a sleepover or their parents can just pick them up. Hope this helped!