Tommy walks in the cafeteria and sees what he thinks, is Jack flirting with his crush. Jack is one of his best friends and he can't believe he would do such a thing.
Tommy was so full of rage that he walk straight up to Jack and punched him in the face. Jack dropped to the floor, in shock. But before anything could get out of hand, a teacher steps in and takes them to the principal.
While waiting, Tommy confess that he saw him flirting with her. But Jack reassures him that he wasn't. Actually, he was putting out a good word for Tommy. Tommy apologized and understood not to assume right away.