I have many OUs set up in my tree for different departments on my campus.
Under each OU is an OU called Workstations. I would like to import user
workstations into the workstations OU under each main OU.

Does this make sense. I started to make policies under each OU, but can
only make it work if i associate it to the ou and the server, but then other
users were authenticating into that OU as well.

What should I do to solve this?