My goodness I could have written this about my son about 4 years ago now. He's a third grader and does do better. Heck his teacher in kindergarten had a thing where she'd send a green square, for good behavior, yellow square, for having problems that day or red square, for the child requiring some sort of intervention or punishment that day, home daily so we'd be more informed. He always got an N for controlling his emotions and self on his report card. It was so frustrating!
Well we just worked on it and worked on it. We saw that he was naughtier during station time so we came up with a plan that she'd be close by during station time. Basically we figured out that boredom was a huge problem and he wasn't challenged. Also he loved computer time. If he didn't get a green square the day before he wasn't eligible for computer stations that day. That made a huge difference in him. He still loves computers too much.
In first grade they started to divide the kids up based upon where they were. The 4 teachers would kinda circulate and in the main subjects they'd have different difficulty levels. That helped alot. He was always put at the highest level so he'd be at least a little challenged in everything. Reading he was already at a fourth grade level though and there was only 1 other child that was... so that class remained a problem but we just worked on it.
But what I really recommend is keeping in constant communication with the teacher, get a plan and make sure you son understands it and understands what his ramifications will be for his actions, Make sure he is kept busy and at his level. If they are presenting him with stuff that is easy my son I found misbehaved a ton more.
This year so far he's gotten all 1's and only one quarter did he get an N for controlling his behavior. I know to alot that isn't perfect but going from getting red and yellow squares constantly in Kindergarten to never even getting calls and only once getting a note this year is fantastic in my book. I'm hoping 4th grade is even better. I think alot of it is pry just time and consistency. But know you aren't alone. There are other moms dealing with this. hugs!