I don't think this is a major part of the equation. Most states have at least a six year textbook purchase cycle. Often they try to stretch it out even further

I don't think this is a major part of the equation. Most states have at least a six year textbook purchase cycle. Often they try to stretch it out even further than that. Let's do a Fermi calculation: 6 subjects x 1 / 6 of a text book per year x 1.1 for lost or destroyed textbooks * $200 per book = $220 in textbooks per year per student. For scale, Mississippi has the lowest average spending per pupil in the nation -- $8,130 as of two years ago. Granted there's workbooks and software too, but if you look at the budget of a school district, the lion's share is going to district personnel not books or computers or electricity or anything else external. Disclosure: I work for an e-textbook company.