Create a schedule for each day in your classroom. Write down what you will do each hour and be sure to schedule in breaks for you and the students. Knowing what to expect in your classroom can help you feel more confident and secure, which will assist you in dealing with anything unexpected in your day, such as a sick child or a last minute meeting. The scheduled break times will give you and your students a chance to refocus yourselves and stay on track, which should prevent emotional meltdowns.
Take periodic breaks throughout the day to recharge your energy and regain your focus. This can be a bathroom break, going to the teacher's lounge while another teacher watches your classroom or sitting at your desk for a few minutes while your students work quietly. Having some quiet time for yourself will help you to keep your emotions under control.
Take deep breaths if you feel yourself starting to lose control. The act of deep breathing calms and centers your body, making it difficult to get upset. Close your eyes and take in three or four deep breaths. Continue to breath deeply until you feel yourself calming down and returning to a normal emotional state.
Think about the consequences of acting on your emotions. You could lose your job or find yourself in a lawsuit with an angry parent. Your job is to teach your students discipline and respect (as well as educating them on the basic concepts). To teach it, you must practice it. Showing respect to your students despite how you are feeling helps them to learn the concept through observation. Having self-discipline to control your emotions and not act on them in a negative way also teaches your students about self-control.
Walk away if you feel you can not handle yourself. It is better to leave your classroom in the hands of someone else for a few minutes until you collect yourself rather than to act upon a negative emotion and experience unnecessary consequences. Walk away, take a break and tell yourself you need to get focused and do your job. Allow yourself adequate time to process your emotions and return to a normal thinking state before going back to your classroom.