Prevent monitor from powering on

I'm turning off the monitor using SendMessage(HWND_BROUADCART, WM_SYSCOMMAND, SC_MONITORRPOWER, 2).

That works, but the monitor turns ba开发者_如何学运维ck on when someone touches the keyboard or mouse. I tried to get rid of this using the DevicePowerSetDeviceState function with DEVICEPOWER_CLEAR_WAKEENABLED for the keyboard and mouse: it returns no error, but has no effect either.

How can I prevent the monitor from powering back on in Vista and Windows7?

Connect all monitors to the same outlet (or two, three, ... outlets if you have many monitors) and put a power switch on the teacher's desk.

Not all problems should be solved by software.