Do not do this at school

Do not ask to go to the bathroom in the last five minuites of class

You: (raises hand)
Teacher:(nods)
You: may I go to the restroom?
Teacher:( turns into a gigantic flame dragon) NO YOU MAY NOT WE HAVE FOUR MINUTES OF CLASS LEFT
You: never mind I don't have to go anymore
You: may I go to the office to call my mom
Teacher: what for
You: new pants