online textbooks waste of money anyways
Online textbooks are not a good fiscal choice no matter what. it's cheaper to budget replacement books every 10 years or so. If a course has material that changes faster than that, don't use a textbook. There is plenty of information that can be collected via the Internet or other means for free.
If the commercial publishers won't play nice with the kids then expel them for not fulfilling the contract or at least for being idiots. I bet there are a few authors more than happy to write textbooks for tthe district with anual updates for the exercise problems. I know of a few university and college programs that have gone that way already.