Tourette's/behavior issues

[My2boys]

I'm new and I have 2 boys that have TS. 13 and 7. The youngest we are struggling big time with behavior problems at school. Not mean but he struggles with finishing work, talking, goofing off , focusing, staying still and listening to the teacher. We have become so frustrated and are trying to find ideas to encourage better behavior with positive reinforcements. We have had to imply negative consequences but its not helping. I need some input I'm ready to pull my hair out and I'm sure is he frustrated as well. Our oldest never really had behavior problems so this is new. I also posted a question regarding adding new multivitamin to help them maybe, cognisense or any thoughts? Thanks so much!