Ultra, I've encountered enough fabulous teachers for it to reinstill my faith in public education. May this teacher be one of those.
If your kid is like mine,my caution would be against doing anything that looks like your child is being asked to do more because of his level. My kids tend to view that as punishment for being smart. This goes 10000 fold for anything that's writing.
My approach for out-of-the-box accommodation requests are for the material/instruction be something that a child wouldn't get in school otherwise. I've gotten some creative accommodations by asking that the teacher give my kid "that stuff that you wish you could teach kids but don't have the time. Here, we've got time? What would you love to do?". DD got some great comparitive history projects and poetry assignments last year (5th grade) and DS has done some pretty cool mathy projects. In each case, the teacher modified the instructions of an existing assignment such that it wasn't much more work for the teacher and it didn't look like extra work to my kids.
