Schools used to hit people who got an answer wrong.
Hitting people for being wrong is very un-Popperian!
A) it doesn't help them create knowledge
B) mistakes are common (among everyone, adults too)
C) finding mistakes is good! they should celebrate. why connect it to pain?
D) they see the problem like this:
we KNOW the answer. the difficulty is how to suppress disagreement (which must be bad, because it's mistaken, b/c it contradicts the KNOWN TRUTH). in other words, we know what ideas should rule, and the only thing left is to enforce their rule.
of course Popper would prefer this problem: we have some ideas about the answer, and they may be mistaken, and by discussion with people who disagree, and culture clash, and self-reflection, and criticism, and by a serious effort, we may learn something about our mistakes, and come nearer to the truth.