We never had a book mobile here in East Tennessee, but we did have RIF. RIF was a acronym for
Reading
Is
Fundamental. They would come in, rearrange a few of our lunch tables, and spread literally a thousand or more books on the table. Each student was allowed to pick a book for free. Everyone was looking for books about bugs or with lots of pictures, and I was looking for H. Rider Haggard

.
We also had the Scholastic Book Club, with their forms to order books from. Our family wasn't exactly rich, but my mother typically never had an issue with my wanting to order at least one book when these order forms were released to the students.
I think Dolly Parton has something that travels this area that has to do with books and reading, though I am not entirely sure what it is all about.
Wow, this awakens all kinds of memories. School libraries were regular haunts for me. In my pre-teen to early teen years, I would walk miles into the forest to find a suitable tree to lean on and read. Reading by a stream or a river, and losing all track of time.
But, to this day, I do not care for public libraries, and even most college libraries.