Student input
I too beleive that student input is important to a certain extinct. It is important that students are able to express their feelings about what they are learning as long as it doesn;t cross the line or interfere with the objectives.
Student input is critical, because when a student formulates responses to class assignments, he or she deepens those wrinkles in the brain. The test of whether learning has occurred is the student's performance. The student's input also gives the instructor feedback about how to improve the lesson.
I also think feedback is very important in constructing future lesson plans. It's good to receive feedback from the students, or it can come from colleagues. Sometimes you can just tell whether or not something worked, and you can make adjustments for the next time.
I'm going to agree that feedback is useful after the lesson is taught. I'm not sure how useful it would be before - I'd be concerned that the student isn't exactly a subject matter expert; if they were, they would be in the field, not in my class. Afterwards, though, I like knowing if the lesson made sense or stuck with them.
An example of student contribution, I ask at the end of some lessons to submit 2 question that would be aligned with a quiz on the material.
I sometimes will do a short pop quiz at the end of class and the results are great because all the information given that day they remember. I teach in a culinary school and I will do this short 5 question quiz on the food ingredients and methodology. Then I will open up the floor for discussion and my students are not afraid to discuss the quiz and are so engaged.
