Someone, sometime on mumsnet gave a tip about creating a "busy box" - it didn't make a lot of sense to me at the time, but I remembered in and in desperation this week tried it out on my 5 yr old. The result was fantastic! So thank you whoever you are.
If anyone else wants to try it. You write out on bits of card suggested activities for your child. Then when they are bored, or you think they are about to start behaving badly, you suggest they dip into the busy box, for a more suitable suggestion. In ours we've got; Lego, K'nex, playdough, painting, baking, play with puppets, jigsaw, HAMA beads, play Kerplunk, junk modelling, face painting ... loads more, I can't think of.
I know it just sounds like me making suggestions, but it REALLY WORKS - he goes off and does something sensible and structured, and has a great time, instead of causing mayhem.
I think originally it was suggested to have pink cards for activites with mummy, blue ones for things on his own, green ones for things with his little brother ...! Well, I may get that organised for next holiday ... In a parallel universe maybe!
Of course it could just be that Christmas excitement has worn off, and he's adjusted to the routine of NOT being at school (just in time to go back!), but he really has been a reformed character for 3 whole days now since I made the busy box .... AND IT ONLY TOOK 3 MINUTES TO MAKE!