Thanks Scruffy and MisterMe
Unfortunately we have serious problems in getting this Apple lab to authenticate to the student sub domain; we have created a single student account for each machine and wish to lock the desktop so as to keep things clean and consistent for the generic "Student"...
Working in a school I am trying to lock the desktop so students cannot make changes to the background or change/remove/add shortcuts. I know you can lock the dock but how about the desktop itself?