F is for…Fresh air. 
You have a break in the middle of the morning for a very good reason. You will have been concentrating hard and your brain needs time to rest before you carry on learning for the rest of the morning. Lots of children like to stay in, and they ask their teachers for jobs, but the most useful thing you can do for your teacher is to go outside and breathe in fresh air to wake yourself up. Also use this time to eat a piece of fruit, have a drink and go to the toilet, so that you come back to the classroom refreshed and ready to carry on learning.
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