We started the school year with video games and movies, but only on non school days. A month in we had a open house at school, and that is when I learned he wasn't turning in his work. We started checking his backpack, watching him do his work and put it in his backpack. A month or so later we had parent teacher conferences, and found out that he had turned in his homework for a couple weeks, and then stopped. He was grounded for a week, then his teacher said he was turning stuff (including a lot of his missing stuff)in so he was not grounded anymore. On Tuesday he brought home a progress report, he had 1 D and 2 F's. All because of his missing work. This time he is completely grounded from all electronic things for at least 2 weeks, maybe longer.
But I don't think this will work, he will turn stuff in for a week or two, then stop. He is in danger of having to repeat 4th grade. He can do the work, he does most of it, he just never turns it in.