Wow, you all are describing my DD to a "T". She's in 3rd now, and we're still trying to get an accurate diagnosis, but she has had school issues starting the very first day of Kindergarten. Basically, the same things you described - impulse issues, complaining of boredom and not wanting to do the boring stuff, fidgety.
Her Kindergarten teacher was great and really worked to find things that helped DD get through the day. The thing that worked the best for mine was the teacher drawing her a little picture on an index card that said something like "Great Job!", etc. If she had a bad behavior day, she didn't get the card and that really upset her and motivated her to do better. Maybe there's some small daily reward you can work out with her teacher?
I would suggest, also, looking into getting her fully evaluated now. We've been waiting for almost 9 months to see the only Developmental Pediatrician in our city. For us, the issues have gotten exponentially worse every year and I wish I had started this process a lot earlier now that I'm seeing just how long it can take.
