Default [Q] Sharing internet from PC to Android via dongle

To preface this question, I do NOT want reverse tethering as I am not rooted and currently rooting is not an option.

I am a teacher. My school does not have wifi, and obviously you can't install software on the computers. However I often have the need to use apps on my tablet that require a network connection. What I'm wondering is this:

Suppose I get a cheap USB wifi dongle somewhere. Is there a program that I can install onto my flash drive (think Connectify) that will allow me to broadcast a wifi signal via the dongle? As far as I am aware, Connectify can't be used from a flash drive (but I may be wrong).

Thank you in advance!