You've done your Chuck E. Cheese's, your Fun Fest, your rain-soaked birthday party at the neighborhood park. And there's no way you are going to subject your own home to the kind of abuse 30 5-year-olds can cause after the giant Jaws bounce house you promised doesn't arrive on time. What you need is a seamless, low-maintenance, high-energy, modestly priced, kid-tested alternative to the mind-numbing childhood ritual known as the birthday party. You can find it at ASI Gymnastics, with its seven ground-level trampolines, its carpet-bonded tumble floors and its giant foam pit. Curb service for your store-bought cake and decorations, which can be any theme you bring in, from Sesame Street to Harry Potter. The first 60 minutes will be spent jumping and running and swinging and tumbling with coaches who are both cool and safety-conscious. The next 30 are spent in a private room with cake and pizza or whatever you decide to import. The best part is, ASI provides the cleanup. If they could only dispose of the 30 gifts that your child is dying to get his hands on and doesn't really need.