Install drivers for every UNO we have?

Hi All,
Here's the situation I have and hope you can shed some light on: I'm setting up a computer lab (at a university) so our students can use Arduino UNOs with Matlab/Simulink.

I can plug in the UNO, install the drivers and everything works fine... until I try it with a different Arduino board (We have many; lab has 24 PCs.) I have to re-load the drivers from the Device Manager. It will then work, using a different COM port. If I use yet another different UNO board, the drivers must be loaded again. I'm not inclined to install drivers at every PC for every UNO board we have...

I searched and read past threads about the UNO's Vendor ID and Product ID. Is this how Windows (7) knows the difference between these boards??? Is there a way to make them all equal in the eyes of Windows, and just use the installed driver? (There are no situations where more than one UNO would be in use at a PC at a time.)

Any help would be appreciated,

I'm surprised you have to do it through device manager - once the drivers were installed for me, it automatically installed them for a new board that was plugged in (so that if the IDE has been installed with the installer, it won't even need a manual installation step).

The clone boards with other serial adapter chips may be better behaved in this regard... Windows seems to be able to tell arduino boards apart, but it doesn't seem to be able to tell CH340G's apart.