Answer:
Watches students at the prom to make sure there's no funny business.
What comes in many varieties and can't be seen or touched, but it often makes you move?
What is all over a house?
Other terms for this handy device include doohicky, doo-dad, and whatchyamacallit.
It's been around for millions of years, but it's no more than a month old. What is it?
What language does a billboard speak?
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?