Adding administrative rights to a Group

I have a Domain (NOBLE) and I have a Group in that Domain called (Students). The actual students use 18 PC’s running Win XP in a lab. Each student has their own username and password and they log into the NOBLE Domain. The Student Group has limited rights but now need administrative rights just on the PC’s in the lab in order to have the ability to do some of the things that an admin on that computer can do. How do I log into the 18 PC’s (into the NOBLE Domain) and give the students admin rights ?