Jim Meola is a seventh-degree black belt in goshin jujutsu, a Japanese martial art. He instructs cops and soldiers, and even devised a system, called Combat Jujitsu, for the U.S. Army Special Forces. None of that, however, prepared him for teaching children. That just comes naturally. "I really enjoy it," says Meola, whose school takes kids as young as five. The father of two young boys, Meola is a master of holding short attention spans and making lessons meaningful and fun. Whether invoking the Power Rangers or describing all-too-real scenarios involving strangers, he neither talks down to the kids nor over their heads. His program "is Americanized in that it has to be entertaining," he says. "You just have to take into consideration who your audience is, in addition to the traditional side of teaching a 2,000-year-old art."