As been said before your best bet is to ask the admin, if you know who he/she is, what firewall they use. More than likely they will tell you, especially if they feel comfortable it is patched and configured properly. On the other hand, the admin may be hip to folks asking questions about outer perimeter devices and will shoot you the bird and tell you to go lick a firewall.

I am trying to get my school system to change the server becuz i find exploits in it.

Are you referring to changing the firewall or another server within the school's network? I'm a little unclear about that. Why would they replace or change the server when all they need to do is patch it to fix the exploitable areas?