I think he's overwhelmed. Somewhere along the line he got "off track" and needs help getting back on track. It's too overwhelming for him to get it going again and so it's easier to "put his head in the sand".......poor thing.
If he doesn't have a homework planner, I would get him one. Binder clip it open to the week he is working in. Teach him how to be organized. This planner can remain on his desk so he can easily write his homework assignments in it when the teacher announces them. Tests/quizzes inlcuded. Also, contact the teacher to let him/her know his troubles. this is not uncommon, but they should be aware that it's happening to your son and you need to work together. As he gets older, school will get more difficult as teachers will begin to expect more from him responsibility-wise. He needs help now to be ready for future years.
I also put a folder in my sons backpack labeled "mom". This folder allows my son to put anything in there he is supposed to show me. This way he doesn't have to remember until he gets home :o) That is working great in our home right now.
Contact the teacher, if you cannot wait for the conferences about this time of year. send an email asking his/her routine for homework. Is homework written on the board each day? Math every night? spelling due thursday? social studies wed night? tests every friday? You need to know what to expect your son to have homework-wise each night. And the teacher needs to know that your son is gong through this.......sometimes teachers are more forgiving and understanding if they have good communication from the parents.
Sometimes I needed to be "cheerleader" for my son to get through this. I stood next to him reading the questions and he would write the answers. I didn't DO his homework, just simply let him know he wasn't doing it alone. I was support. Only 2 weeks of this and he learned that it's not as bad as he thought and he can do it alone, but it was HE that had to know that in order to carry on a routine. It gave him a feeling of accomplishment, which gave him back some self-confidence with his homework. wheew!
As far as routine, I would re-establish a homework routine in your home. afterschool allow him a snack and 15 mins to unwind. Then straight to homework. at his age, he should have no more than 45min-1hr at the longest depending on how fast he can work. a school handbook usually states this. this will take dedication from you to help him, but it will be worth it to get his homework habits back on track.
If it were my son, I'd go easy on him.....just support him and tell him what you expect of him and that you ARE going to help him, it's not a choice :o) I firmly believe with your attention, he can overcome this and get back on track.
I don't think anything has "happened" to create this situation for him, I think it's normal. Puberty is starting for some his age and emotions for boys are the first to trigger (aside from the voice changing)....at least with my son his emotions were like this earlier than other boys in his class.
My son is now in 8th grade and has continued his homework habits after we "hit them hard" in 4th grade. I just spontaneously check on him, but we still follow the same routine.
Good luck through this difficult time. You will find your way to help him :o)
~N. :O)