What should I do if I didn't do well in the exam and the teacher asked my parents to sign it?
Parents still have to sign, but what's your question? From your question, I feel that you are a kind, sensible, self-respecting child. In fact, this is also your precious advantage! If the exam is careless or does not perform well, you can make it clear to your parents. I believe this kind of low-level mistake won't happen again next time. Let them rest assured that they care about you and love you. If you really work hard and do the same, then make it clear to them sincerely. As parents who care about and love you, they will also make plans for you early. Remember: communication is also an opportunity to learn and exercise while growing up!