It definatley makes the class go smoother when youhave all your materials prepared & ready. Coming into class diorganized sets the mood for the students and they become distracted & unfocused. Unfortunatly it can sometimes be tough to have all classes fully prepped when they run back to back & labs need to set up. We often share a lab & dont have the luxury of alwasy leaving materials out until we need them. Having the students help prepare the lab as part of it is one way I can get around that.