When I first started teaching there was only one kind of mount readily available, the Daessy Locking Swing Away Mount, and as far as I'm concerned it is still the best. (I wish I could junk all the others in my room.)
I haven't tried them all, however, so here are some links to peruse when it is time to assist in choosing a mount for a student. Just remember 1) you don't have to buy from the company the device vendor is pushing and 2) the more adjustable it is the more likely it is to move when you don't want it too.
- CJT Technology (wheelchair, desk, walker and other types of mounts)
- Daessy Mounts (wheelchair and desk)
- Gus Mounting Systems (wheelchair)
- Help Mate (wheelchair)
- Mydesc (wheelchair, bed, scooter)
- RJCooper (wheelchair)
- Assistive Technologies (reseller)
- 3rd Hand Mounts (wheelchair for small device and custom made)
- UniMount (wheelchair)
- Simplicity Wheelchair Mount
- ADA Lap Wheelchair Tray and Accessories
Check out this picture below to see what it used to be like to mount an AAC device (actually an Apple II computer)!
And just for kicks here is a photo of one you could make yourself.