what does "give him six" mean?

Probably derived from corporal punishment. To get 'six of the best' was to be hit across the hand six times by the teacher's cane.

I speak from experience being the day boy champion of getting the cane at school.

"Gave him six" means that the captain of the eleven gave the school poet six blows with a spiked running shoe.

At many schools, it was the arse, not the hand.

Not in Australia, always the hand, in England's beano comics it was always the arse, which is the country I'm guessing you're referring to because you said arse. Doesn't seem to be a part of American school life. To be fair it was banned in most of Australia by the mid 90s.

I didn't go to Eton (my parents weren't rich) but when I was a boy my father's Conservative-leaning newspaper (the Daily Express) often had interviews with and stories about the headmaster of that school, Anthony Chenevix-Trench. In those more deferential times people like that were "looked up to" and their opinions sought about all kinds of things.

Anyhow, he was forced to resign and after his death a lot came out about his liking for private caning sessions and sexual assaults he carried out on boys. He was not unique. This sort of thing needs exposing, like the priests were in Ireland.

The Beano is from Dundee.

I told you the Scots were good at stuff.

Actually I hated Beano - but without it Viz wouldn't have been as funny.

I think the old IPC comics, Whizzer & Chips, Cor, Buster etc had at least as much to do with Viz as the DC Thompson stable.