I'm sure that Apple would want iPads for every school student, and I certainly applaud the Bring a Browser philosophy which suggests that ICT is becoming something a student is responsible for, like their bicycles or their uniforms (with the obvious and important caveats for equity etc) BUT it is also clear that an iPad is the most wonderfully collaborative screen. There is something about a laptop screen that crates a barrier - and about a trackpad + keyboard that says "single user", when a multi-touch screen with no fixed orientation says 'share me".
In this photo of children at the wonderful Holy Rosary School in Claremont, Tasmania you can see, in the foreground, four children sharing two laptops; one is 'driving", the other is watching in each pair. But the group behind shows four children around one iPad, sitting NSE&W and all engaged, taking turns, sharing, collaborating.
This picture is what i see often and it is one of many reasons why iPads (and presumably other tablet devices one day when those tablets catch up a bit) work so well, even a few at a time, in the classroom