Oh this is a big one! Sounds like there is a lot more going on between the lines.
I haven't got much time but will try to come back. Boys in early highschool can be very contrary then they can suddenly blossom.
Boys respond to praise, praise, praise. Describe every little thing he does that you value or admire. "I like the way you asked your teacher about that problem. You're very good at finding solutions to these sorts of things. I like it when you apply yourself to your homework it makes my day so much easier..."
Lay it on thick but try not to patronise. You might find it sounds false or you are overdoing it but it becomes more natural. It might help to write down the behaviour you want to see and then some phrases you could use so you don't have to think on the spot.
Good luck.
JA
