Of all the books I've read about education, a few have made such an impact that I reread parts every year (or more often if I need inspiration). One of those books is called The Power of Our Words by Paula Denton.
As I reflect on professional development that I have lead or attended, I realize that sometimes we math teachers are a little too focused on math. Not that the content isn't SUPER important. However, the culture of our classroom, structures we have in place, and the words we use have a huge impact in how our students learn that math. If students don't feel calm, safe, and respected, they won't be willing to take risks or persevere.
This is where The Power of Our Words comes into play. Some things I've learned from Denton is to resist voice-overs and to avoid personal approval. A voice-over is repeating a student's answer or thought for the class. This causes students to look to the teacher for what is important and not listen to each other. As for personal approval-- it's just a small change. Try saying "that is an interesting method to solving that problem" instead of "I like that method." If we want our students to be successful in making mathematical arguments and critiquing the reasoning of others, we need to let that happen and not always be the center of attention in our classrooms.