The Computer’s Nerd by W. Royce Adams

Bullied and mistreated by three schoolmates, Arthur thinks his computer and a strange program called “The Game” may hold the answer to his problems. The Game allows him to secretly get even with his tormentors, but when The Game begins to go too far Arthur fears he may get into even bigger trouble. And to complicate things, he finds himself becoming interested in and confused by Natalie, a girl in his class.