While teachers of course are senders—they deliver information in a clear and age-appropriate way to their students—and students are receivers of that information, it is imperative as a teacher to listen to and observe your students carefully and at all times. They are providing you with invaluable information about what they know, what they want to know, what their strengths and challenges are, how they learn best, and so on. You cannot be an effective teacher without being at least as good a listener as you hope your students will be.
In a classroom, who is a receiver of messages?