A popular game to play at a sweet 16 birthday is musical chairs. In order set it up, count the number of participants, and place one less chair. Set them up back to back so that the players can dance in a circle, and start playing music. The rules are simple: find a chair to sit on as soon as the music stops, or you are out of the game.
Another fun game for a sweet 16 birthday party is balloon truth or dare. Write out 10 dares plus 10 truth questions on small cards, and place them in balloons. Each guest participating in the game has to pop a balloon and either complete a dare or answer a question truthfully.
Alternatively, it's also a good game idea to rent a karaoke machine, and have guests display their singing skills. Choose songs that are popular with the guests so that they already know the lyrics. If you want to lighten up the atmosphere and get everybody talking, then try out the lie detector game. For this, give each guest a pen and paper. Get them to write three facts, of which one has to be a lie. Next, ask each participant to read out his facts so that the rest of the guests can guess which of the facts is untrue.