Answer:
Watches students at the prom to make sure there's no funny business.
Proof you've done your time in school
Long and thin, red within, with a nail at the end.
This is the main ingredient in spaghetti and Mac-N-Cheese.
They are Dark, and always on the run. without the sun, would be none!
If it’s information you seek, come and see me. If it’s pairs of letters you need, I have consecutively three. What am I?