That's four demerits, four hours extra kitchen duty.
4 seconds sound clip from the The Sword in the Stone (1963) movie soundboard.
You can hear this line at 00:17:55.428 in the Blu-ray version of the movie.
Quote context
[...]
- After all, I took him in, adopted the lad, you might say. Being his foster father, I'm responsible.
- Tiger, Talbert, off with you.
- That's four demerits, four hours extra kitchen duty.
- But, sir, I'd like you to meet...
- Go on, hop it, boy. Hop, hop, hop it.
- You've got to keep a tight schedule to run a big place like this.
- You need strict rules, especially for small boys.
[...]