For Enzo, the Fourth of July means three things: fireworks, family, and car races! This year Zo Í¡is finally old enough to compete in the Kids' Kart Challenge. But when one of the boys at the track says that girls aren't fast drivers, Zo Í¡gets nervous and backs out of the race. Enzo knows it's up to him to help his family regain the confidence to compete on the big day.