When a student tries to open one of his Revit drawing files he is getting " kilometers per second square"d message and won't let him get in.
Units errors like this usually result from trying to save a file to a disk where there's not enough free space (like a USB flash drive, or full disk drive).
If the network drive is full, you could save-as to the local machine or a flash drive. Other than that, there's nothing you can do. I've only ever seen the error when the drive was full. I've also seen it as square feet per foot, and inches to the fourth, etc. For some reason, Revit returns a disk-full error as an impossible units error.