Hi everyone, I need some help

I work at a school as the ICT person. We have 2 Digital mac class rooms right next to each other. I have only ever used a mac here

Room A has 16 Macs that all hate me.
Room B has 17 and loves me. They are fine. They have no issues. I want Room A to be just like Room B.

All of the Macs have deepfreeze running on them (using an image set up by an external company who does the stuff I can't figure out) and they all have the same image on them. They also all connect wirelessly. they are connected to like this (the rooms are in a line)

(5xPC's) Room C (AP) | (16xMac's) Room A (uses room C's) | (16xMac's) Room B (AP) | (10xPC's)Room D (uses room B's)

What they do: some always wont find the wireless (with DF on or off) and always promt for the wireless password at log on, some appear connected, but then take forever to load pages, but more often then not will just get to a 'could not connect to (HTTP) Proxy' page. We use schoolzone here, and I have checked the proxy settings, it is configured correctly, and plus it does sometimes load pages. One never gets on the internet ever.

Room A computers were in another room last year and played up with the wireless and i put it down to the router being dumb. But they were moved this year so that cant be it. I got a EIT classmate of mine who is much more Mac then me, and he looked in logs and couldnt find anything. We tried turning off Room C's AP to make it use the same one as the good room, didnt work.

Interesting point: The teachers macbook works fine. my friends macbook goes fine. my windows laptop works fine. but when all the computers are going, they all start to exibit the same wireless on off symptoms. We had the idea that maybe one Mac was somehow messing with the rest of them.
So thismorning I tried doing them one at a time. Teachers laptop fine. first mac i turned on played up, so did 2 3 4 and 5, all turned on by themselves. Teachers laptop keep working throughout this little test (set up two pages redirecting to each other to test a constant connection)

I can post system specs later (have not got them infront of me right now) but if anyone has any ballpark ideas as to what the heck might be going on, I would really appreciate it. They are driving me crazy!