It Wasn't Me! by Michael Bond

Imagine swallowing a computer chip and becoming a living computer . . . Imagine almost burning down your school . . . Imagine being Harry Manners. He is a very unusual boy. His family don't understand him. His teachers wish he would stop daydreaming. But he thinks he's doing just fine, as long as he has a stash of Max Masters comics to read and his imaginary pet pig Monty to take for a walk.
Binding: Paperback / softback