“So what do you do all day...play?” As an early childhood teacher, I’ve heard this question hundreds of times.  I smile knowingly as I respond because, to be honest, I understand. Glance over at a group of children at play and how could you think otherwise? These children are chatting and laughing, completely engrossed in their materials, and having a blast. How could this be considered anything except pure fun? To understand what’s really happening here, we have to look a bi