Three brief thoughts on this: 

1. People are calling it “banning books,” which it ain’t: a book isn’t banned by being left off a reading list; 
2. One teacher says, “I think it’s time to allow books published from the 2000s to be given a fair shake” — because sure, the big problem with our society today is that we just don’t give a “fair shake” to new things; 
3. Of the nineteen books listed above, eleven of them were published between 1925 and 1967 — nine between 1938 and 1960 — which suggests a certain constriction of imagination and the dominance in teachers’ minds of a quite brief period in our cultural history.