I am wondering the same thing.  Finding this answer is the only way I would use Khan lessons. 

Seriously Khan, if we are going to use this effectively for our students with learning disabilities, we need to be able to hide the grade level so we can empower students.  This should be a priority fix.  Have they responded to this inquiry yet?

While KA has been emphasizing subjects by grade, there are still sections available based on math subject (arithmetic, geometry, pre-algebra, etc) outside the by-grade areas. From the learner pages, the sections are found by choosing "See all Math" under the Courses menu and scrolling down past all the grade sections. Similarly, if you edit your classroom setting on what courses you're teaching, the non-grade math choices are listed under the by-grade choices. I imagine if you made the assignments via the non-grade areas, your students would be kept in the by-subject area instead of being redirected to the same subject in a by-grade area. Thus hiding that a student is working on a subject usually considered more elementary. Hopefully that helps someone.

Hi Shaila, 

Thanks for the reply to this pressing need. I tried this and it still show "3rd Grade" or whatever grade when you try that approach. I'm a special ed teacher in high school also and I need to be able to teach my kids third grade math without something saying that this is third grade math. If there's not a good workaround, I really won't be able to use Khan. I think it's great for the teachers to be able to see grade levels, but definitely not students. I agree this should be a priority fix. 

Two years later and I don't see anywhere that says this issue has been fixed. There are still special educators looking for resources with no listed grade level...like me.