Our library didn't carry Nancy Drew/ Hardy Boys etc claiming they were fomulaic and basically the equivalent of "brain-candy". Unfortunately my mother agreed. So I borrowed them from my friends!
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In terms of dated expressions:
When I was quite small, I read a book called
B Is For Betsy.
In Chapter 1, Betsy is about to start school for the first time. She is going to first grade (this was written in the pre-nursery school and kindergarten days). The boy next door teases her about the switch in the corner and poor Betsy is quite worried. I could never figure out why a light-switch would be frightening!
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Back to brain-candy, I had the same issues with my daughter reading those Babysitter Club books.