Software to disable internet proxy for classroom

Our labs run WinXP and we have a teacher's PC in front, with about 40 student pcs in a class room. I would like a software that will allow me to disable my student PCs during my classes so that they cannot surf the internet. The teacher's pc now has a software called Netop (search google) installed to enable freezing the student pcs or locking the keyboard or showing students my pc's screen. The Internet Explorers go through the school's proxy. I want to be able to launch a software on my lecturer's pc, that can see all the students logged in (by pc name ID) and I can use a check box to click some or all of these PCs and disable their proxy (or change the proxy to something else) so that the internet access is stopped. Once the class is over, I can enable the proxy back OR if I forget to enable, once I close the software, before it closes, it will automatically enable the proxy back. Windows XP, any software to create this application is ok. VB? ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Windows XP, any software to create this application is ok. VB?