I have a funny story,
DS1, went off to uni a couple of years ago, He is autistic and dyslexic, so finds other humans behaviour challenging as they are not logical , a couple of weeks in , he phoned me, to tell me a little shocked that people were not paying attention in lectures, he found it very distracting and upsetting, he really couldn't understand why anyone would do such a thing.
So we chatted about some of the things he might do to improve the situation, the sorts of things suggested on this thread, I also knew he was well liked by his fellow students, his personality is such, most people really like him immediately (despite him being really odd), so I suggested that he could have a chat with students but not in class, that were misbehaving and explain to them how it effects him, appeal to their better nature, worth a shot,
a couple of days later in one of the lectures which had the disruption problems, paper chucking and smart alec remarks started, so DS1 who was sat at the front remembering our conversation,
He stood up, turned round and announced, 'Anyone who is talking, throwing thing and spoiling the lesson can come outside and discuss it with me', total silence, so he said, "OK then, but if anyone wants to, let me know and we will go outside', sat down the tutor thanked him,nice quiet lesson,
The thing is DS1 is 6' 8'', and built like a brick shit house, he does a lot of sport, he had no idea that it sounded like he was inviting them all outside for a fight,
he was so pleased with response he repeated it in all his classes when people were being disruptive,
It was only when his friends who had realised his intention was just that have a chat with everyone, he is so fluffy and would never start a fight, told him, he realised it sound like he was going to beat them all up.
But no one disrupts in any of the lectures he attends anymore.