Tell my how will you clesr up this misunderstanding. Thnks !!?

Explain the misunderstanding. If your parents knew about it they could back you up. Ask if it's possible if you could stay in at a lunch and do another assignment. Even though you knew it wasn't your fault. Explain the story and say that you'll be willing to do an alternate punishment. That way, it shows that your not complaining and that your being mature even if you don't get what you wang. Hope this helps!