Which of the following is a common classroom management technique?

Establishing clear expectations is a fundamental classroom management technique because it creates a structured environment where students know what is expected of them in terms of behavior and academic performance. When teachers communicate their expectations clearly and consistently, students are more likely to understand the rules and the consequences for not following them, which helps to minimize disruptions and enhance the learning atmosphere. Clearly defined expectations also empower students to take responsibility for their behavior, fostering a more positive and productive classroom community.

In contrast, the other options may have their own merits but do not serve as primary classroom management techniques. For example, assigning more homework may not directly address behavioral issues and could potentially lead to student frustration. Reducing classroom size can help with individual attention but is often not a feasible solution and does not directly involve students' understanding of expectations. Increasing recess time, while beneficial for physical activity and social interaction, is not a direct method for managing classroom behavior and expectations.