Can't keep myself out of trouble at school?

I have ADHD and I just can't behave at school. For my bad behavior last year I have been given a 90 day probational period meaning if I do something bad during that time I get expelled. I feel really bad about myself and I have a reputation of acting stupid at school. I'm a relatively smart kid academically and I don't want to be expelled. I need some helpful tips and guides please give thorough answers. Thanks

About me:
Love minecraft
13 years old
Rising 8th grade
USA

If the class is so boring you can't focus, maybe you can ask the teachers to give you some work (like books to read, essays and reports to write, math problems to solve) to do during class. You should also try to learn to control yourself better. Small kids can't, and then they learn and they can. Stay away from chemicals the school may try to give you.