Although my last trip, my outbound flight was shared with a group of about 20 18 year olds coming back from Thailand on a 6th form trip for 2 weeks. I had the poor luck of being allocated a seat in the middle of them for an 8 hour flight plus a 1 hour delay on the Tarmac.
For me it was a 2am flight after an 11 hour working day, urgent booking so that morning hadn't even known I was travelling, so hadn't done my usual early night the night before a redeye. I was bollocksed and needed to sleep.
They treated it as a school coach, up and down talking to each other, kneeling on the seats to talk to the person behind, shouting up and down the cabin.
I did the grown up thing, ordered 2 large whiskies, and sent myself to sleep. Got about 2 hours over the whole journey.