Nicholas Pinto may be one year away from high school, but he’s already doing big business. The 13-year-old says he’s always loved scooters, but was frustrated by how quickly the wheels would break. “As you develop your skills, like landing on the scooter harder when you’re going off of a ramp, what you want is for the parts not to break,” says Pinto, who lives with his parents and three siblings in Cranford, New Jersey. He says he was spending a lot of money replacing the wheels every few weeks. “I was saying, ‘Wow, this can’t be!’ I was trying...