Calvin Williams was tired of seeing kids suffer head Injuries while playing soccer. "I had so many friends who made their children quit the game," says the Houston real estate developer who has coached children's sports for years. Soccer players can get serious concussions from directing balls with their heads, colliding with other players, or falling. So about four years ago, Williams decided to do something about it. After scrutinizing numerous studies on head injuries, he came up with a soft helmet for kids.