The legal way to do this (without bothering the author) will be to buy the model multiple times (once for every student you plan to provide the model to) and explain to every one of them what they can, and can not do with the model they receive, according to the Royalty Free license.
The same applies to individuals who buy a model to include it in a project and are required to provide the scene files - they have to buy another license for their customer (who will have the model).