For my 13th birthday party I did not know what to do.  Unfortunately I found myself running out of time.  I invited about 6 friends and we had fun together, and I realized that a birthday party doesn't need to be super expensive to be super fun. A party is like a reason to get together with your friends and have a good time.  At the beginning of my party (4:30 PM) we made ice cream sundaes. It was really fun, and we had three types of ice-cream, different types of sprinkles, sauces, chopped nuts, and cherries.  We even had bananas for banana splits! Then we had fun creating the most creative sundaes we could (sponge bob square pants sundaes, and more).  A good thing to do when you don't have much to do is to take out fun group games.  Suggestions are games like charades, truth or dare (make sure everyone is comfortable w/ the dares and truths) or a fun card game like spoons.  I had made waterballoons for the party but found out that nobody really wanted to get wet because it was getting cold outside at 5:30.  I suggest if you want to use waterballoons, tell your guests in advance and make sure to do it when it is not too cold outside. We decided to go to the swim and raquet club just up the street to play tennis (I'm a member). Make sure you have enough raquets and stuff like a Frisbee, or football to toss around if people get bored of tennis.  When we came home it was about 6:30 or 6:50 and we ate dinner.  Afterwards we opened gifts and played scrabble while watching Never Been Kissed and eating popcorn and M n'Ms.  We ate cake after that (we were really stuffed!) and continued watching the movie and playing scrabble.  I really enjoyed my party because my friends and I had a lot of fun, although it wasn't that extravagant. My friends made the party fun.