Caps for Sale by Esphyr Slobodkina has been in print for over 50 yeras and was a storytime favorite of mine when I was a kid going to library programs.
Even though it's an older book, it's super interactive and so clever. (NOTE: I just read the reviews on Amazon and a few people complained that the publisher cut some text and refrains so it's shorter than the book I remember from my childhood. No complaints here though!)
This flannel works best with a helper to arrange the pieces while you read the book.
Caps for Sale:
A peddler (cap salesman) walks up and down the streets trying to sell the many caps he keeps stacked on his head. He decides to take a nap against a tree one afternoon.
At this point, I would turn the flannel board around and have the storytime helper arrange the pieces for the next scene.
When he wakes up, his caps are gone. He looks to his left, he looks to his right, he looks in back of himself, he looks behind the tree, and finally he looks up and what do you think he sees?
Every time he asks for the caps back, the monkeys mimic him - first he shakes his finger, then he shakes both hands, then he stamps his foot, then he stamps both feet, and finally he get so angry that he throws his own hat on the ground and the monkeys throw down their caps too.
This whole part is really interactive with the kids.
This flannel is one of the sets I remade while on maternity leave. Bigger and better! My almost 3-year-old has been having a blast with personal storytimes: