In most school environments, some amount of record keeping is required of teachers, such as noting which students are absent, taking a count for lunch or handing back completed homework. A teacher can minimize these times by developing classroom systems to handle much of this record keeping. For example, you can provide an attendance sheet for class, asking students to sign in as they enter the room or create a filing system for completed homework, allowing students to pick up their graded assignments between classes instead of during class.
Emergencies such as bathroom breaks and students' requests for hall passes to go to the nurse take up a teacher's class time. For mature students, limit the distractions these activities cause by allowing them to manage their own bathroom breaks and nurse visits, leaving class without a word when they need to handle these situations. For younger students, keep hall passes in a convenient place during class, so you can hand them out quickly and return to your lesson without much delay.
When discipline issues arise -- such as having to break up students engaging in fights or arguments during class -- they often require immediate attention. Take a proactive role in limiting such problems by restructuring class seating, placing students who regularly present discipline issues in the front of the class, in your “action zone.” This is the area of the room where the instructor most often faces and interacts with students directly. The proximity of an instructor can deter students from many distracting actions during class, limiting the non-instructional time dedicated to discipline.
Student attention is sometimes redirected to distractions such as other students talking, visual stimuli around the class or activity outside the window. Limit these distractions by closing the blinds during class and removing overstimulating images from walls. Develop a solid introduction for each lesson, engaging students with a message demanding their attention, getting them interested in the lesson and making it clear you are beginning the lecture. Draw class to attention the moment you are ready to begin and get students used to focusing attention on you during class.