Justin Bieber -- Ballin' Out ... For the Kids (VIDEO)

Video proof here Justin Bieber can dominate in yet another sport, 'cause he put on a soccer clinic ... against a bunch of pre-teen kids.

No, Justin wasn't being a jerk -- even though he did literally dribble circles around some of the tykes. He joined the kids for a pick-up game in the park next to the fancy Bev Hills hotel where he's staying ... and you can see the parents are loving it just as much as the kids.

In this clip alone, JB scores twice -- complete with his own "gooooooooal" celebration. But he also lets a kid steal the ball and score on him.