Hi Edward: Students do expect their teachers to be subject matter experts. The best way to assist students learn the needed information is being there for them to facilitate learning and provide answers when they need help. When the lessons are preplanned, resources set-up, materials ready, these actions convey to the student the teacher is ready and prepared for the class. However it's done, we want to convey to students we are there for them, to contribute to making their learning a successful experience. Regards, Barry