""She sells seashells down by the seashore."" You may know the tongue twister, but do you know the story? In this silly STEM Twister, kids explore what would happen if a girl sold seashells down by the seashore. How much would she sell them for? What would she do with the money? Paired with resources for teachers and caregivers, this book brings math concepts to life and gets kids excited about concepts like money and calculation. The STEM Twisters...