The Trescott books is very good. The G1000 user manual that you can get online for free isn't too bad, but very mechanical and boring.
The G1000 simulator from Garmin is pretty good. Ultimately, it would be great to get students out to the plane and sit there with external power o. A bumpy, hot, noisy airplane is a hard place to teach people how to use all those little knobs and buttons. If they have a chance to play with them on the ground, that'd be a huge advantage.