New iMacs--New way to login

In the MS labs (not including 7th grade at South) we have 25 new iMac Machines....quite an improvement from the eMacs :)
Students and teachers will need to login to a machine to gain access to programs and the server.  For teachers, they will use their badge # for the name and for the password their server password.  Students will use their lunch codes for their names and a password generated by the network administrator. 
There are a few logistics about logging into a lab machine that is different than previous lab machines.

• Each time someone logs into a machine....it is like they are creating their own desktop (they can individualize their desktop-pictures, dock, etc)
• If a student has saved a bookmark on the #1 lab machine on Monday and sits at #2 lab machine the next day it will not be there as they were sitting at a different machine the day before
• The IP address will need to be set when a student needs to save to the server--once a student adds it to the list....it will be there the next time he/she is at that machine
• 10.239.70.44 is the address for our server--have them click on the + and it will save to the list
• Your thinking....why?  Students and teachers will now be logging into their own account.  My understanding is if a student goes to a site that is inappropriate....it can be tracked by the network administrator.