...the same character narrates the whole book, but in two distinct timeframes - there are past and present events, with a clear distance between the two? Preferably with one of the narrators being a teenager?
I suppose Brideshead Revisited would be one. Is I Capture the Castle? No, maybe not.
Anyway, I am trying to do this in my writing and wanted to read some good examples, so I can spot what works!
My original thread is here, thanks to those who advised me 
www.mumsnet.com/Talk/creative_writing/3613652-Structural-help-needed-please