Price per year per student licensing that exceeds the cost for purchasing an equivalent textbook is outrageous. There are packages that actually make fair use of the technology distribution model to take the cost down to significantly less per student per year vs. physical copies.

In theory with an iPad a motivated student can follow a lecture and do enrichment work with the iPad. It's pretty tangible and engaging. Some of the reward based math games are cool. DS and I have played with casting technologies where a each student in a class can answer quiz questions during a lecture. In that way a teacher could get a quick guage of understanding levels.

We got one as a lark at Christmas (trying to burn one overly generous relative's Christmas money without disrupting our plans.) I'm confident DS7 would've kept up a decent pace in math without it, but I don't think that in six months he would've taught himself math partly through algebra with a supporting understanding of statistics and a mental model of the core concepts of calculus without the iPad. He's torn through podcasts, videos, timed activities, 3d graphing applications, fractal simulators, physics simulators, chemistry simulators, etc.

BUT, I think they are close to worthless in a classroom without self-starter kids or if the teachers are not getting full, consistent, and ongoing professional development on the use of the technology.