If you have both a computer and a PS2 then get a broadband router. the MAC address of the router will get registered. any other devices connected through the router don' t need to be registered.
If you only have a PS2. you need to borrow someone's computer that has a programable MAC address ethernet card. program it with your PS2 MAC address then register it. (or someone with vmware works too.)
Or you can ask the school IT stuff to add your MAC manually, but that depend on the school policy on connecting non-computer device.
PS2: NTSC 39001 V7 + Messiah 2