What does it mean when they say to read a book of merit?

Question

It's for a summer reading thing and I just want to be sure, apparently not a lot of people know what it means either.

Answer 1

It means a book that has won awards, is well recognized, and basically isn't a piece of c**p.

Answer 2

A book of merit is a book that has some value to it when compared to all the other books that are also available.

Answer 3

It sounds to me like they want you to read a book that's considered to be intelligently written, and has some standing in the literary community.

My guess is they said that because they don't want people to use "Twilight" or the "Clique" series, but they don't want to come right out and say it.