In my experience many teachers shy away from the idea of 3D printers because of their lack of knowledge around the industry. They don't know how to work with CAD, don't truly understand how they work, and can't see how useful to education a printer can be.

Teachers need to be educated about these printers, the software, and possible applications and lesson plans around these devices. Once they see what can be printed, most will jump on the bandwagon.

The Makerbot initiative to give free printers to teachers received an underwhelming number of responses from teachers I have heard. Why? Because the teachers don't understand what these machines are capable of. It's up to the schools themselves to bring this information to teachers, and for parents to push the administrators to do so.

Just my experienced opinion.