Is it forbidden for a student association to sell human bones and skulls to students, knowing that these are exhumed from graves?

It is permissible to use the organs of the deceased for a legitimate purpose, such as training and medical experiments, but it is not permissible to trade in them. If they cannot be obtained except by purchase, there is no sin upon the buyer, and the sin is upon the seller. Those in charge of these activities can purchase these bones and skulls as agents for the students and then sell them to them, if they cannot be obtained otherwise than by purchase.