Have 3 boys: 15, 17 and 18. From experience, they have all "whacked out" for a few months somewhere around 4, 5, 6th grade. Their brains and bodies are getting ready to grow, and some are more in tune to social things/ pressures going on at school. Doesn't mean let it all go, by any means---just know that they get kind of goofy for a while.
here's what worked for us: yes, homework planner or academic notebook to write things down and due dates and everything....
Our kids had to show it to us every night while they were getting the hang of it.
Little "chill out" time between school and homework....whether that's sports, a music lesson or running around shooting a basketball for a few minutes. Boys, especially, benefit from a short break before hitting the homework. This was not TV or video game break, though.
One area to do homework. Kitchen table or work table in the dining room or second hand desk or something. Big key: let your son set up the homework area---it's his. My youngest had the hardest time getting organized with homework until we bought a desk at a yard sale and put it in his room. He picked out a lamp, bought pens and pencils and wanted a couple crazy desk things (rubik's cube, lava lamp) for it. But it's his and we shut our mouth and let him set it all up.
We only allow TV or video games after all homework is done. Set a firm ending time, though. They are now all in high school and have so much homework, that the screen stuff rarely occurs during the week.
For our youngest, if he turned in all work during the week and did his best job on it, and did not forget work, he got a special something on the weekend.
(This took some doing---my husband is a "punisher" and I am a "rewarder." My youngest responds much better to rewards than threats of punishment.)
We made pizzas on Friday night if he did everything he needed to, or we made brownies OR he got an extra half hour of video game or TV over the weekend if he took care of all his school responsibilities.
That's what worked for us.
Good luck and God Bless.