This openhearted and energetic documentary opens up the competition of the World Karting Association for audiences who don't realize that go-karts today are sleek, road-hugging machines that can go 80 mph and put middle-school-age drivers on track to enter NASCAR. Director Marshall Curry knows just where to point his camera to clarify the tension of each race. And with his loving and intimate coverage of three competitors -- ultra-disciplined Josh and unsure neophyte Annabeth, who race against each other, and the heartbreaking wild boy Brandon, who drives in an older division -- Racing Dreams becomes one of the wisest of all recent films about the pressures that shape American children's personalities and fates. It's a bit like American Teen on wheels -- except its characters haven't hit their teen years yet. It's also, often, very funny.