Yeah perhaps the school has a code of conduct regarding the "ethical use of necromancy" with guidelines on what can or can't be done. Perhaps there are people who donate their bodies to the school for use this way, like raising the dead for use in manual labor around campus. There could be certain rules like when and for how long a corpse can be raised, skeletons must be cleaned fully before raising, zombies must have appropriate attire for their intended use and must wear face obstructions to preserve identity privacy of the deceased. Perhaps long standing zombies must be submitted for inspection of structural integrity and upkeep?