I remember reading all of the "Mrs. Piggle-Wiggle" books when I was a little girl, along with all the other little girls in my class. We took turns borrowing the books from the school library and absolutely LOVED the stories of how Mrs. Piggle-Wiggle helped frazzled parents by finding creative ways to get their kids to wash their ears, make their beds, and do a host of other chores that the kids normally just couldn't stand doing. The only other fictional character that even approached Mrs. Piggle-Wiggle's popularity among me and my female classmates was the famous Pippi Longstocking. I think I saw a few boys reading Mrs. Piggle-Wiggle once in a while too, whether they admitted it or not!
As an adult, I think this book contains some great lessons in persuasion as well! Simply ordering someone to do something rarely works - but if you can show them that it's fun or to their best advantage, that works much better.
I'm especially pleased that this box set includes the original dust-jacket designs by the illustrators Hilary Knight and Maurice Sendak. I'm not a big fan of using different illustrators for the cover of a new edition of a classic children's book. I'm giving this box set five stars, and the paperbacks having a different cover fewer stars.