I am not a doctor but have been there. I have 4 children, 3 boys and a daughter. My son’s 28, 24 and 15 years old. My 15 year old son is ADHD and ODD. He has been on medication since he was 2 years old. My son did the same things you mentioned. He takes Adderall and Risperdone. It has not been an easy task but has gotten better the older he gets. Not sure how things work in Canada but you need to tell the school, you want your child tested. After that an IEP or section 504 this will help with behavior and educational problems. My oldest son is ADHD and has tourettes, my 24 year old son, ADHD either one of them had the ODD. My son that is ADHD and ODD is a freshman in high school. I went to teacher-parent conference at the beginning of the year. His teachers said to me, they thought my son had an attitude problem. Why they thought that, he always has a straight face. He hardly ever smiles. I informed them that he has always been like that. Drives me crazy, I would ask him several times a day, “are you ok” “is some thing wrong” “are you feeling ok” he would get mad at me and say why do you ask the same questions day after day. You might try to find sometime when it is you and him and ask him how he feels and why he does the things he does. I know that my son didn’t respond like most children would when it came to discipline. Time outs, grounding him, take things away I was about to give up. We negotiate everything, I get what I want and so does he.