I remember watching this both times it was shown on BBC1. To precis IMDb's entry, the lead character, Jimmy "Fish" Barnes was an unpopular kid and very much an outsider, whose life changed when he found a stray dog. He had dark hair, an awful haircut, and heavy, black horn rimmed glasses. Jimmy, that is, not the dog. I can't remember the dog. I recall vaguely that he was considered a bit of a nerd: he lived with his older father, not much money, no trendy clothes or toys. I think it ended up that he ran away for some reason, but finally gained acceptance when he was found.
Do You Remember Fish?
Do You Remember Fish?