A fellow teacher just shared these with me:
Dewey Decimal Pictograms
They are awesome pictograms that would assist students in finding information on the shelves. I have to say I was pretty impressed with them, thought partly that is because the library is in a state, and needs a lot of work. This would make things SOOOOO much easier. Students would find it easier to find books, and, if I placed these on books as well, it might be easier to put them back. It is an interesting thought.