So DS1 has been gaining a reputation over this term for naughtiness which has culminated in him being sent more than once to another class (penultimate punishment before head's office). Today's offence was doing star jumps behind teacher every time she turned to face the whiteboard. He got laughs and kudos from his playmates and a huge telling-off (of course) but nothing seems to make him actually change his behaviour.
In truth the class is full of boisterous boys and there have been several whole-class punishments for misbehaviour over the last year. For a while it all settles down and then a few children start mucking about again and generally encouraging the others to follow and the whole cycle starts again. DS1 is, unfortunately, an instigator in this along with about 4 or 5 others.
What can I do at home to get him to understand how disruptive his joking can be?