There are units that can be installed vertically to shoot downward at a table. With the aid of eBeam, the unit can turn a tabletop into an interactive map for learning U.S. capitals or planning a siege on a tyrannical dictator. Projectors that have front exhaust and rear intakes would do miserably in this scenario. The heat would come out the front, rise and finally be sucked back, causing a heating nightmare. That being said, such projects are good for horizontal installations where units need to be pushed to the rear wall without effect.
Color accuracy may be the last thing you’re concerned about. However, there are some teaching scenarios where color can be extremely important. For instance, companies like Canon have projectors that adhere to Digital Imaging and Communications in Medicine (DICOM) standards that give accurate grayscale reproduction. This is essential in teaching someone how to interpret results of an MRI, CT scan, or even the results of sonar being used to determine where subterranean oil reserves may be located.
A school for graphic design, film editing and production will have similar concerns about full color spectrum.