They already have this con set up too well
the bookmakers and schools already have a gentleman's agreement about this; you make it so that your students require our books specifically, and we will continue to release new editions so that the books aren't tradable and must be replaced. Unless the book companies can get their cut, I don't think they would play ball. This would allow the bookstores to make profit in addition to the markup (craaaaaazy markup) already on the books. I think the book makers would raise the price to reflect this.
Also, if this becomes a traded asset, some ass could manipulate the price, making the coins the school holds worthless, or making books too expensive for students to afford. Also, someone with superior mining power could hoard coins and restrict the supply to drive up the price. Wouldn't take a ton of money to corner this particular market, it would have a known total capitalization.