I have been concerned about that. Unfortunately I pay my bills by working in a factory 2pm-10pm which makes shorter but more frequent events for teachers problematic. Luckily plenty of universities offer that kind of 3D printing instruction so at least if a teacher wants instruction spread out over time where they can "do their homework" and come back to the printer that exists.
My event is an attempt to help curious novices get a solid understanding of what they need to learn more about to become an expert. I think 28 hours with 5 different make and models of printer allows a lot of understanding to develop.