Your'e correct that the trope isn't simply "Children's books where somebody dies." But you're not
correct that the defining feature is "it's about such books that win awards, are widely assigned in schools, are praised and touted by adults."
The trope is plot and characterization trope. I've bolded the important parts of this (extended) definition:
"There is a Slice of Life story about childhood and coming of age
. The main character has a best friend
(an animal, another child, or a family member) who is a source of joy, wisdom, and understanding in their life
. This friend is often frailer, more unworldly, or otherwise more "special" than The Protagonist. Bonus points if the character is cute or adorable.
At the end of the story, this very special best friend is abruptly killed off
, usually in a clear-cut case of Diabolus ex Machina. A favorite trick is to have the death happen entirely off-screen. The more horribly poignant the tragedy the better.
All this is generally accompanied by lots of "end of the innocence" angsting from the main character, along the lines of "That was the day my childhood ended..."
Really, it's just the author's way of having a child suddenly make the jump to adulthood via a single defining tragedy.
Whether a book has won an award or not is irrelevant to whether it's an example or not.
edited 22nd May '14 5:07:51 PM by Madrugada
...if you don’t love you’re dead, and if you do, they’ll kill you for it.