OMG, homework is the worst! My son also has short-term memory problems but, because his handwriting is so bad, he doesn't want to write anything down so he does his math in his head. His ability to do his homework waxes and wanes with his other symptoms. When he is having a bad time it takes sooooo long to do homework, and sometimes I just write a note to the teacher saying that we'll have to finish it over the weekend. Unfortunately, he's not very stable yet so we have week to week and even day to day changes. (One night he had me write on his paper that "[he] is very stressed out about homework." For some reason after writing that down he was able to do his homework, and he turned it into the teacher that way.)
We put him in a new school this year (private) that is especially for special ed students. I love the flexibility they allow! He's pretty good in math and science, so he takes those with the 9th graders, but behind in language arts, so he takes that with the 7th graders. (He's in 8th grade.) Also, we try to keep in close touch with the teachers--I let them know if he's having a particularly difficult time and they let me know if they notice any changes in his behavior in school.
We've found that finding the right school has made all the difference in the world. This year is the first time he's been happy to go to school. He used to sit in the car and cry many mornings before finally getting out and going to class. At his last school we tried to describe my son's problems to the special ed director. Her response "We all have our little challenges." Agh!