The thoughts of a teacher\'s pet

I am a teacher\'s pet, I\'m diligent and well-read,
But nobody knows that all this work wreaks havoc in my head.

I may work hard in every class, and always have good grades,
But those marks can\'t be achieved without my knives and blades.

I\'m always punctual to my classes, moving swiftly across the floors,
But even so, it\'s a mystery what I do behind closed doors.

I smile sweetly at my peers each and every school day,
But in my head I want to die, I\'m worthless anyway.

I am a teacher\'s pet, and forever shall I be,
But only for so long can I hide my scars, in places they can\'t see.