Some actual student bloopers...
Q: What is the plural of potato?
Q. Give the opposite of "filly."
Q. Give the opposite of woe.
Parasites are the inhabitants of Paris.
Q: Name the five continents.
A: a, e, i, o, u.
Q: Name a cow that gives a lot of milk.
Source: V. Shanley's Classic Classroom Clangers, 2000