Sounds tough! I'm with jojo, what works for us is avoiding going for extrinsic motivation (rewards, punishments, praise, criticism) and going for intrinsic motivation and cooperation (why do you want him to behave the way you do want? how will it make people feel? what difference will it make? how does this part of the world work? what's difficult for him about behaving the way you want, and how can you work together to overcome the difficulties?) For my DS5, once he's in non-cooperation mode, anything that smacks of manipulating him makes things worse. He's quite adept, though, at seeing other people's points of view. For example, I'd talk to him about what the teacher's job is like, how she doesn't always have time to think about exactly what would be best for him to do because there are other children who need attention, etc. I'd talk about how the teacher's job is to tell the children what to do and the children's job is to do it, even. If the work is too easy, would he be receptive to a suggestion that he try to do it as quickly as possible? Or that he suggest to the teacher some harder variant?