Mike, I learned what I think is my most valuable lesson from a college professor, but in a negative way.
In the last weeks of my last semester of my elementary education degree, a math methods instructor was waxing philosophically on the importance of getting to know your students personally. He stated we should have a home visit with each student's family and maybe a dinner/snack -that we should bring. And, we should try to complete this within the first quarter of the year. Besides the knowledge we gain of the students' home life, the personal touch builds a parents-teacher bond that gets the parents more vested in the child's education.
I asked, if we had a large student population, say 60 or more, if a social gathering, like a potluck might be an alternative. He became very agitated, and ridiculed my question with something like, "Sixty?! Why not make it eighty?? Why not a hundred?!" and a more words that I can't remember because I was so embarrassed. Then he ignored the question and went on with other topics.
See, in the 70's in elementary school, classes were self-contained. One teacher taught all the academic subjects, and class sizes were usually 20-25 kids. He did not know that I had just been offered a job upon graduation in an elementary that was going to departmentalize in the upper grades. I would teach all the math classes in fifth and sixth grades, plus the identified gifted fourth graders (plus some science classes), about 80 different students.
That stuck with me. I have never put a student down for a question or comment. If I think it doesn't make sense, I remind myself that while it doesn't make sense to me; it probably makes perfect sense to the student. So, I ask questions till it makes sense to me.
Sometimes the comment/question really doesn't make sense. That is when I have to work even harder, asking more questions till the student starts to see, then the light goes on and they say something like, "Oh, wait, I meant to say ..." or similar.
Never leave them hanging in front of their classmates.
Getting the students to the point they are not afraid to give a wrong answer in front of classmates was probably the single strongest teaching technique I had going for me. It opened insights into the minds of how the students figured things out.