Money Games
Use fake money to create a dare game for 12-year-olds. Give each player one $10 bill to start the game. Write down dares on small slips of paper and place in a bowl. Each player can get one dare out of the bowl at a time. If they complete the dare, they earn another $10. Some dares can include "sing the chorus from your favorite song," "stand on your head for 30 seconds" or "show off your favorite dance moves." The player with the most money when all the dares are gone win the game. Alternatively, the party guests can buy prizes like gift cards and items from the dollar store using their money. Place the items on a table with an amount for each one.
Obstacle Course
Create an obstacle course for the preteens. Kids can weave through cones, jump through hula-hoops, balance on boards, jump rope and knock down a large cardboard box wall. Time each player and the player with the fastest time wins the game. If you have enough items to make to identical courses, allow the children to compete in teams. The team who completes the course the fastest wins the game. Make a water obstacle course on a hot summer day by having the kids crawl through plastic swimming pools and run through water sprinklers.
Contests
Many preteens love to show off their talents so host a karaoke or dance contest. Rent or borrow a karaoke machine if you do not have one. Allow the kids to perform in groups or by themselves. Give everyone 20 minutes to practice their dance, song or combination of both. After 20 minutes, everyone must perform and three adult judges will decide on the winners. Award prizes for best dance moves, best voice, funniest dance moves and loudest voice.
Funny Games
Have the kids get into groups of three or four. Peel a banana for each group and cut the banana into several pieces. Give each team a box of paper clips and a roll of tape to try to put the banana back together. Tell the teams they have five minutes to put it back together. After five minutes, the team with the best banana wins the game. Another idea is to divide the players into two teams. Have each team lay in a single file line on the ground with their head at the feet of the player behind them. They must pass the banana from feet to feet down the team line. For example, the first player in line must place the banana between his feet and lift his legs over his head to pass the banana to the feet of the player laying on the ground behind him. The first team to get the banana all the way down the team line wins the game.