A huge push in the latest effective teaching research is student engagement. One way to keep students engaged is through hand signals. Madeline Noonan, a fifth grade teacher, demonstrates several hand signals used throughout her entire school (https://www.teachingchannel.org/videos/classroom-silent-communication-signals). When I was a math coach for Math Matters, they also had a set of signals: don’t understand (moving hand over head), agree (thumbs up), disagree (moving hands across each other back and forth), can’t hear (cupping the ear), etc. When I taught I also added some of my own: sharpen pencil (hold pencil in the air), bathroom (sign language letter B) etc. When we were doing math I might say, “Show me on your fingers the answer.” If we were doing test prep and the answers were A, B, C etc., then I would have them show me the sign language letter for their answer. The great thing about hand signals is the students have quick access to you and you can read what is going on in the classroom, and it all happens silently. However, the most important thing is they can participate and be engaged in the lesson.