ok, my problem with this is replacing books with ipads. the ipad itself will out date every yea, possibly 2, and tech wise, become almost unusable in 3 due to apple forceing os migration.
a book, unless its cutting edge science class, will last 10-20 years, and over all, if there is a MAJOR breakthrough in how we know science form grade 1-12, we can make a copy and give it to the kids.
over all its cheaper to get a new book than to get an ipad every 3 years.
at the very least get a program that is universal, as in ipad, laptop, and so forth. that way there is choice. i would be @#$%in @#$%ed if i had to pay even 200$ for one of those over blown pieces of @!#$, much less 600$ every 2-3 years or 2400 total for rending the thing.