Have you tried switching your laptop to projector or extend mode using the Windows key + P shortcut?
Press
+P at the same time. Notice this brings up multiple options for display, selection one of the options. Try each one until it looks normal.
If you can't find one that works on that, plug the projector in and right click on your desktop, select Screen Resolution. From there pressing Detect should let you know which number screen is your laptop and which is the projector.
Click the relevant number and change the Resolution drop down to the Highest point, if it's too small then try the setting below, - repeat until it looks normal.
If you can't see any of the options above then you're probably using Windows XP, if that's the case let me know.
A final point, do you have an IT department in your school? They should be able to help you with these settings. Me explaining the steps here make them a lot harder to grasp as apposed to someone at your side explaining it.
1When you say "blows up" do you mean your resolution increases drastically? Have you tried changing your resolution? This would usually happen if you are plugging in a secondary monitor with a drastically different resolution than your GPU likes. – Matthew Williams – 2014-03-24T14:10:00.640
1my guess would be your 'displays' are mirrored, and the laptop is matching res with the projector. – Journeyman Geek – 2014-03-24T15:05:41.403