It's actually not very hard to re-set between the adult...

It's actually not very hard to re-set between the adult novels and the ones for younger readers. The narrative voices are very similar, the smartass attitude, the environmental battles. Kids love books that are irreverent and challenge authority, when authority is arbitrary, greedy or foolish. They also love it when you make fun of grownups, and I've spent my whole life as a writer doing that.