All superheroes have one thing in common: They like to stay active. And the superheroes at your child's birthday party are no exception, so be sure to have plenty of games for them to play.
A good place to begin is by asking them to use their X-ray vision. Put a variety of small items in a box (ranging from grapes to plastic water guns) and see if the guests can gauge what they are by feeling inside the box without looking. Older kids may get a kick out of a surprise, such as a half a tomato (cut side up) or other items full of interesting textures. Another inexpensive idea is to cover several small buckets or large-mouth containers in aluminum foil to serve as planets. Then have guests toss ping-pong balls that have been painted green (do this a few days before the party) into the planets. These kryptonite balls can be thrown from varying distances, depending on guests' age and perceived difficulty level.
It's also a good idea to set up different activity stations, each with its own game or craft, that will offer a fun take on the party's superhero theme. In addition to the games suggested previously, wrangle a couple of volunteers for face-painting, using specially formulated paint from a craft supply store or online retailer. At another station, offer superhero-themed coloring books, markers, stickers and superhero cardstock cutouts.
Ask the adults to join you, as you dress as a superhero, too. They may find themselves having just as much fun as your smaller guests. After all, you've already put a lot of effort into planning the party. Now it's time to enjoy it!