Lime's advice ⤵
First of all, I'd like to say that you're an amazing person for loving yourself, no matter what the society's standard of beauty is. You seem like a very talented girl who will have a wonderful and exciting future waiting for you. Please remember this fact clearly: you have done nothing wrong and that it was the teacher's problem for scolding someone without realising what had actually happened; you shouldn't feel guilty or bad about that incident. For your friend, I don't know whether he/she talked to the boys to purposely get you in trouble or not, but please know that you have all the rights to cut that person out of your life, and to speak out the truth to the teacher. As for the boys, they sound extremely immature and stupid; they will have their consequences for their wrongdoings, so please stay strong and ignore those silly comments. You are amazing, and I believe that you can destroy this stupid beauty standard.

Sabby's advice ⤵
You really shouldn't let the teasing get to you! There will always be immature people (not only boys) who will do things like tease others and cause trouble. The only thing you have to do is ignore them. I was in your position last year, but when I got fed up with the teasing, I ignored them and they stopped bothering me. I think if you just try to focus on yourself and the happier things that surround you, then you'll be able to ignore them just fine and they'll eventually stop. A lot of people like that (bullies, internet trolls, etc.) only continue what they are doing because they are given the attention they want. About your friend, I don't think a true friend would want to get you in trouble. You should probably confront her about that. As for the teacher, don't you worry about them because teachers will always end up pointing the finger at the wrong person. It happens at my high-school too haha. I hope this helped. Take care of yourself, beautiful.
 

Pong's advice ⤵
First of all, I know ignoring these immature teasing is not an easy task, especially if you are with them almost everyday of your life. That said, I would still go on and advise you to ignore it. Don't let those empty words hurt you anymore than it already has. You are already amazing just being you and that is a fact. Please love yourself more and forgive those teasers for being immature and senseless. Although I am not aware of the full story, I would advise you to confront your teacher and friends about this. It might bring some harsh words at first, but in the long-run the teasing will gradually stop. Be strong and don't lose yourself to these immaturity!