The commercial license is only required if you are using X-Plane to make a profit, directly or indirectly. You would need to buy multiple licenses for the home use version in order to use it on multiple computers at the same time.
We work with the Fly to Learn program and sell the older versions in bundles with a discount. You might email Randy at
[email protected] to see if there's anything they can do for you on the newest version since it's for a school club.