Mount Volume

On a iMac running SL, I want to automount a network volume and place it on the desktop for ANY user to see. However, I want the student to click on it the mounted volume and enter there own login information. I can add the network volume to Login Items but I want the student to logon to the volume with there own information.

For example, take a network volume called OUSER and I add it to the Login Items. I want Mary (student) to logon to the Mac and I want Mary to see the OUSER (network volume) and I want Mary to enter her username and password.

I want the network volume to be on the desktop regardless of which student logon on to the network. Next, I want the student to click on the network volume and a dialog box appears asking for them to logon.

Do I make sense? I don't want the teacher to ask every student to perform the GO-Connect to Server- logon- select the network volume. I want the network volume to appear on every user's desktop and logon to the network volume.