Spending the first 15 minutes of class providing an overview of the games litany of complicated rules, local ninth-grade gym teacher Marcus Hartwell invented an elaborate sport Friday using just foam cubes, scooters, and plastic mats, sources confirmed. All right, guys, so to score in Jammer Ball, you need to shoot the foam blocks at the other teams mat, said Hartwell, adding that teams receive one point for cubes landing on either the left or right sections of the large blue folding mat, and three points if a cube lands in the middle. If you fall off your scooter, then youre out, unless your goalie catches a cube thrown by the other team and tags you back in. And if you shoot a cube into the basketball hoop, you automatically win. Okay, lets count off by fours and make teams. At press time, after students had expressed some initial indifference and confusion, the game had reportedly gotten so intense that Hartwell had to separate two ninth-graders on the verge of fighting after pushing one another off their scooters. 