...Less talk, more shooting...
^^This.
Powder burner shooters will generally be amazed at the excellent triggers, lack of noise, lack of recoil and their ability to hit whatever they aim at from pretty much the first shot they take.
What kind of targets are you planning on using? As shooters they may be just fine punching paper. But if you have any reactive targets (spinners, Know Your Limits, etc.) those are so much fun with airguns. I would also recommend setting up some Charms Mini Pops for them to shoot (smacking one sounds just like smacking a squirrel's noggin), but this being at an indoor range they likely don't want you to sugar coat everything down range.
Be prepared to discuss (or even start off with) muzzle velocity and power, especially if you think that you might have some hunters in the group. Yes our airguns are less powerful than powder burners, but it is still pretty incredible the power we can make just using compressed air as the propellant.
The shooters you are presenting to will likely have experience with guns in a form which is very similar to our airguns. But
the group I am introducing has really shot only with open sights all of their life, and using a scope is very new to them. Be sure to bring any guns you have which have scopes with a forgiving eye box. And/or be ready to zoom way out if someone is initially having issues seeing through the scope. It has become such muscle memory for us, but isn't so for everyone.
It may be interesting to see how many of your 'students' will forget to cock the gun between shots - folks are becoming so familiar with semi-auto powder burners.