This is a fascinating premise for the author to raise. It is not quite science fiction, rather it is speculative fiction, imagining the consequences of a situation and the effect on the characters.
I never felt like abandoning the book, but equally I never felt entirely engaged with the characters or the circumstances in which they found themselves. It all seemed quite unbelievable - the (never explained) science, the unnatural docility of the 'students' and the physical aversion to them felt by the 'normal' adults. The adult students seemed to move through the strangely empty landscape of the outside world without ever interacting with it.
Yes, it is intriguing, thought-provoking and (perhaps) a frightening comment on how easily we could fall into what is effectively slavery, but to me it was never wholly convincing.