Jason recovers...

... from the conceptual bomb Verne dropped, in Chapter 39 of Paradigms Lost!

AKICILJ: The adventure that's forgotten... (with particular attn: James Nicoll)

It is a classic trope of fantasy literature, especially kid's lit: The children are caught up in a big adventure or series of adventures, they save the princess/town/world, and afterwards they forget the adventure when they return to the Real World, except maybe for a feeling of more contentment and some level of maturity/improvement.

Oddly, though, I'm pulling a blank on the stories that actually DO this. For instance, Narnia isn't like this; the children remember their Narnia adventures very clearly.

So what ARE the classic examples?