Dear Joanna.
I read your letter and I am really touched. I even cant imagine how terrible it is to be humiliated infront of all your classmates by your own teacher. I've never been in such situation but I will try to help with some advice.
A lot of kids nowdays have the same problem with you. You just should remember that nobody is perfect and you should love yourself and it does not matter what other people think or say about you. Come up to your mirror and say: "I am beautiful"
But if opinion of your teacher is important to you, you can start working on yourself, it is not too difficult to loose weight at your age (good exercises and diet is all you need). You can change your body and prove everybody that you are a person of strong will and character.
You can also try to talk to your PE teacher, explain how offensive her behavior is. I am sure she will understand you and will change her attitude.
Hope my advice will help you.
Best wishies,
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