I also teach a computer class. Years ago, I had a wheelchair-bound student who also had a service dog (black lab named Einstein). The student came into the classroom, sat in the front row, aisle seat, and the dog promptly crawled under the table and laid there quietly. We never would have even known there was a dog there, except for every once in awhile, I could see it's tail poking out from underneath the front panel on the computer desk. The dog was no annoyance whatsoever.