This Guardian article about what makes a book a classic is worth a read.
So is the list of classics - both those within the article as well as the list at the end. The ones mentioned in the Comments are interesting too.
What are you reading right now?
The Borrowers Afield for us as a bedtime read-aloud. Jemimah's reading Return to Gone-Away. I've just started 44 Scotland Street and finished Passing On. Hubby is half way through Scarpetta. Together the adults are reading A Song for Nagasaki: The Story of Takashi Nagai-Scientist, Convert, and Survivor of the Atomic Bomb.
Goodies in The Book Bag include: The Last Battle, The Penderwicks on Gardam Street, Justin Morgan had a Horse, The Family at Misrule and Johnny Tremain.
There is more than a smattering of classics in there. Maybe some future classics as well?
Talk to me!