You went for school picnic. You were disobedient and indisciplined there. Write and application to the principle apologizing for your mistake and tell how you will behave well in future. Here is a sample for how to write an application?
Name of your school
State – Pincode
Subject : Apologizing for my mistake
With due respect I say that I am a student of Class VII-B request to excuse me for my disobedient and undisciplined behaviour in picnic. I know that discipline is an essential duty of a school student. I would therefore request you to excuse me for my irregularity.
I shall be highly greatful for your kindness. I promise you that I will not repeat it again. If it will be happen again then you can give me a strict punishment. I would there fore request you to excuse me for my irregularity.
Class – Section And Class
Application to the Principle Apologizing for my Mistake