Children sit down for snack in Yellow Door at the MU Child Development Lab (CDL) after their naps on Friday, Oct. 21st. Yellow door consist of children aged two and a half to five years old, seen here from left: Rachel, Brielle, Amelia, and Sophia. The CDL is a teacher-training lab that serves 90 families with children through six weeks of age to thirds grade. One of the key assumptions of the CDL is that children are active and curious. The CDL's goal is to foster those creative learning abilities.