Ooh, easy potshot you took!
A teacher can teach until they're blue in the face, with the best ability and utmost concern for the student. The student must be willing to receive, understand, and internalize. What use have those people had for that information after their standardized tests are over?
Also, that was not a continuous shot. Lots of editing. For entertainment purposes, they cut out almost everyone who knew the answer and left in the respondents with the most embarrassing answers or reactions. Bad sampling, but makes for good TV for those who feed on it.