For my sister's 15 birthday, it had a casino theme.  Everyone got chips when they walked in. We had games set up, one table was black jack, one was tripoley, a card game, and high low, a game we had made up.  There were two dice in a felt covered box, a coin was flipped to determine if you were playing for high #'s or low #'s. Each person then bet however many chips they wanted and rolled the dice, whoever had the highest or lowest # got the chips.  For hours my sis's friend played these games and had sooo much fun, it was a great hit. We had solitaire set on the computer, and if you won, you got some chips.  They also had a "Guess How many candies" you bet on how many candies were in a box, and whoever had the closet guess to the actually number got the candy and the chips. At the end, everyone counted up their total number of chips, and starting with the most, they got to pick from a variety of prizes. This party was such a success, it was the topic of lunchtime gossip for many days!