Never having another kid's birthday party at home, even if the stains did come out of the rug after the umpteenth cleaning? Looking for something more memorable and, God forbid, more meaningful than cardboard pizza and head-splitting video games at the usual locales? For little ones 10 and older, this north Valley shop will host a "Bubblemakers" Party, a terrific and carefully supervised introduction to scuba diving for $250 for up to eight children. It all takes place in the shop's heated indoor pool, with the kids donning gear and experiencing the thrill of hanging out underwater. Partygoers get a "skill certificate" at the end of the day, which is almost as exciting as the obligatory cake, cookies and other goodies provided.