Hey, desperate mom, you could have an equally desperate son. Some kids have terrible memories for things they don't find relevant. I know. I was one of them, and the endless frustration and injustice still have real intensity for me half a century later. I was a "good" kid, yet I got stringently punished for my failures, and you bet I lied if I thought I was about to get assigned yet another dirty job or deprived of yet another privilege or dessert (we didn't have goodies like video games back in the stone age).
What would have helped? I think if I believed my mom actually cared about my experience and really wanted to help me find solutions, something might have shifted. As it was, I had a few teachers over the years who showed me that concern. My 6th-grade teacher called me in for a special conference, told me what he liked and appreciated about me as a student, told me what potential he recognized in some of the work I did turn in, and gave me a few ideas about how to keep track of my work.
I had similar experiences with my H.S. algebra teacher and senior English teacher. I worked my butt off for the teachers who cared about my needs, anxieties, and success. I used the same approach years later when I was tutoring at-risk kids in H.S., with pretty amazing success.
I'm not sure what the precise combination of ingredients would work for your child, because there's not really much information in your request. But it sounds like you're focused on correcting through punishment, and not so much encouragement and reward. If that's the case, I hope you'll google a couple of things and see if any of it fits: "motivation in children" and similar key phrases, and "emotion coaching." There's also a really valuable book, How to Talk So Kids Will Listen, and Listen So Kids Will Talk, that will teach you how to get your son involved in actually helping to solve his own problems.
Also, your son may have a neurological deficit such as ADD, which would really complicate his academic life. Have you ever had him evaluated?