I received an email that addresses Anoka County globally. In my rather random notes, I mentioned that several Anoka branches shelved J and A non-fiction together. Now I know the situation exactly:
"J and A nonfiction interfiling --- this is in all branches except the Northtown (HQ's) and Rum River libraries. These 2 buildings have definite children's departments."
The reason this caught my eye during my visits, I think, is that I grew up in the days when the children's room was entirely separate from the "grown up" part of the library, and there was no way a kid could get to the adult books until probably grade 7 or 8. I like the practice of shelving them together, since kids get to delve into "adult" books--and adults who want an introduction to a subject, or perhaps are not strong readers, can find easier books without going to the "children's shelves." I recall an English Language Learner who wanted a kids' book on tennis for exactly this reason.