I found this book yesterday at the Super Flea, a profoundly depressing flea market out in the suburbs. It is the teacher's guide for two children's books, In the City and People Read, both published in 1965 and illustrated by Dan Dickas. The books are reproduced within the teacher's guide. I don't normally go for this general style of illustration but I think these really work. Grainedit.com features a lot of mid century modern illustration like this.