When I was at school, bribery worked for me! My parents didn't have much education themselves, although my father went to night school and ended up with a BA years after he left school, so they wanted me to have the choice of career that they didn't have when they left school. I was one of those kids who did like school and was too goody-good to have bad mates anyway, but they did bribe me with things I wanted -although I'm still waiting for the horse...
I'm just doing an article on educational ICT tools and that may be the answer for your son. Many kids don't 'get' traditional book-based learning and whereas years ago there was no alternative, now there is. I'll PM you with some website addresses and details. You need to find something that grabs him and keeps him interested. I know he's still fairly young, but have you asked him if he has any idea of what kind of work he'd like to do when he leaves school? If he says "rubbish collector" then you're stuffed, but if he says he's keen on being a mechanic or a computer programmer, etc., point out the skills he'll need to have to get these kinds of jobs. If he really wants something, he will be motivated to get those qualifications.
Yes, I am pedantic about spelling and grammar so get used to it!
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