Why not attach a wireless mouse and pointer device, not a regular wireless mouse but a dedicated presentation type device, to your school lap top which will be connected to the projector.
Now you can wander around the room and control what is on the laptop screen with the device.
A device like one of these, the result of a quick search:
http://www.amazon.com/s/?ie=UTF8&keywords=presentation+remote+wireless&tag=googhydr-20&index=electronics&hvadid=33827015515&hvpos=1t1&hvexid=&hvnetw=g&hvrand=15944596463181941839&hvpone=&hvptwo=&hvqmt=b&hvdev=c&ref=pd_sl_4wbi6f9rb5_b
that help?
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I am a teacher who has been given an old projector with no wireless capabilities (dongle doesn't work). But I have a school provided laptop and my personal 2-in-1 laptop.
I want to be able to walk around my laptop, while still projecting. Is there a way I can wirelessly have the school laptop display my personal laptop's screen wirelessly, so that I can project the screen for the classroom?
Or, do you have any other suggestions (other than buying a new projector)?

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