This document provides guidance for teachers on facilitating student problem solving and reasoning in mathematics through key teacher actions. It discusses posing challenging tasks, being clear about learning goals, and orchestrating mathematical discussions. Some important points are: teachers should select tasks that cannot be solved easily to encourage higher-level thinking; setting clear learning goals helps guide instruction; and facilitating productive class discussions involves techniques like revoicing students' reasoning and using wait time. The overall message is that teachers should aim to create an environment where students can grapple with open-ended problems and learn from each other through collaboration and explanation of their mathematical thinking.