ANOTHER GAME TO PLAY WITH THE HERD- Ball Toss. Would also make a great "rainy day" activity. You could even find tubs or buckets of varying sizes (like nesting bins) for more of a challenge for the older kids (Think Skee-ball).
But with nerf guns DIY Prize Punch. easy and inexpensive game for children's parties. (Uses dollar store supplies.
Bear scout adventure Grin and Bear IT: This site has a bunch of fantastic DIY carnival games and activities. including this simple KNOCK DOWN game. All you need are disposable cups and a cute sign!
Bean Bag Toss - Label paint cans with the numbers or points awarded for each throw. For a fun variation on traditional beanbags, use beanbag animals. Way to use my old paint cans.
East Coast Mommy: Carnival Games and Activities paper towel tube and pipe cleaners!
Make your own fake-barbell for the strongest person alive. Hooray for DIY costumes!