Yes, me too in the 1980s. There was a popular game called 'Rape' in my secondary school - if you can believe that. Large groups of boys would target a girl, and chase her with the aim of pulling her knickers down. Then they would kind of wander away, hands in pockets, not sure what to do next. They generally targeted the pretty girls, and it was considered a bit of an 'honour' to be picked, which is sick.
But I don't think the boys even saw the girls that they terrorised, not properly. Their whole attention was aimed at the other boys, working out where they were in the pack and whether the 'top dogs' had noticed them.
I have accompanied a couple of school trips in the last couple of years. Both had - despite being a good school overall - a really big problem with the behaviours of groups of boys en masse. None of it was overtly sexual or intimidating in nature, but wow it was hard work. I am a mum of two teenage boys, I'm not intimidate by boys and even had a reputation of being pretty strict / fierce in the playgroup days, but wow these kids really tested me in a big group.
The younger boys - 11/12 yrs old, were just oblivious to the adults of either sex, and were completely focused on getting the attention of the 'alpha' boys: the ones that were a bit more developed, more muscles, making smart arse comments. They idolised these boys - jostling and literally pushing to get in front of them, shouting their name to get their attention, fighting to sit beside them, to make them laugh by saying or doing outrageous things. A whole lot of stupid behaviour in teenage boys is done with the sole purpose of making their friends laugh and winning their approval.
The older ones 16/17yrs... much of the same but this time utterly uninterested in listening to myself or any of the other female leaders present, especially when telling them off. But when our tall, bearded, sporty, masculine leader spoke? They paid attention then. It's like they couldn't even hear our feeble little womanly voices, but they could hear his booming shouts no problem. They literally couldn't see some of us standing in a group at 5'2" - but they literally looked up to him at 6'4". And they wanted his approval in a way that just didn't apply to us - they wanted a manly handshake, a clap on the shoulder, a pretend punch on the arm. Again, whenever he was with us they were jostling for his attention. Unfortunately he was the only male on the trip, out of seven adults so he was spread pretty thin.
I would say that the majority of them get involved in this group behaviour.
Anf during all this, the girls are just left to get on with it - because they can be. Because they are sensible, reasonable and mature by comparison.