Check out this cool 3D Printed Stepper Motor that Christopher Hawkins made. You can see in the video that it can move quite quickly and not loose any steps. This design would be idea to teach how stepper motors work.
Via: Hack a Day
“This is a programmable stepper motor and driver that I made out of some nails, magnet wire, neodymium magnets, a digit park microcontroller, and a 3D printed piece that I designed around these things. My goal was to make something about the size of a business card that moved. You can’t exactly fit it in your wallet but it does indeed move. It just a first draft- there’s lots of room for improvement. It has a step angle of 15 degrees (although the way I’m driving it, it is 7.5 degrees.)”
Read More: 3D Printed Stepper Motor