If Apple really wanted to improve education, they'd make the file format open. That way even schools without tens of thousands of dollars of Apple gear could benefit.
On the other hand, the textbook makers currently have such a lock on school districts that I don't feel really bad about this. iPads will only get cheaper.. I'm almost positive kids will complain when they get the shitty scratched up hand-me-down iPad2 the school district has had for 5 years when iPad7 is available -- but I've had worse experiences with paper textbooks. :-)