Those kids were in a live show up in Edinburgh called School of Comedy. There was a big group of them. Maybe about 8. The little kid with the glasses was by far the funniest. He played the same character in every sketch but he'd really refined it - a posh, loud, old guy. And everyone loves kids swearing. They performed at the Pleasance and were one of the best shows I saw (if only because I expected little). In fact, when I went to see them the guys from Fat Tongue (who did the alien sketches) were in the house too. I also went to see them. They were a classic sketch group and TV didn't really do them justice.
Also, who the hell is the guy at the end who does the shitty song and looks like a hideous emaciated version of Julian Barratt and Noel Fielding?