You had better be good cause if you're bad,
Santa will bring you something really ugly and sad.

You won't be a happy camper, in fact you'll be mad,
asking your mom, "what's up," then quizzing your dad.

Parents say get dressed, wear your Christmas plaid,
you say "nope," I will not follow that fad.

They threaten to send you to your room for being rude just a tad,
you sit in your room shocked by the coal in your stocking, wishing you'd been a better behaved lad!

The moral of my rhyme is that it's never too late to learn your lesson and be a good kid, like I bet you wish you had...