@roger,
There could be something too that, roger.
Most of the kids at Mo's school adored the magic kid type stories where the outsider type kid becomes a big hero.
Of course, most of the kids at Mo's school were on IEP's due to their Asperger's.
I get the appeal of "powerless/orphan/foster kid finds hidden ability to persevere and become a hero" genera. I've enjoyed my fair share of them. Mo just doesn't.
I'm going to have to put together a list of books I know he liked and see if I can find a common thread....