My father worked for World Book. How about you?
My stepmom actually still works for Grolier/Scholastic - but she sells mostly to schools & libraries. And even that has changed drastically - she went from selling the reference sets to now having to worry about Harry Potter books.
Mine was Colliers. A step below EB in authoritativeness, a step above WB in the grade level that it aimed at. And as for Americana? Well, they were in the game.
I remember Colliers. I pit Colliers to WB - lol. As we used to say, “it starts at a 3rd grade level, and then each paragraph after is meant to provide more and more detail on higher grade levels - so that each student and adult can progress to the level they are most comfortable/interested in.”
But that’s just a lifetime of WB training.