(related to Part: Jokes)
(This joke only works in German)
The original German Joke is
"Ein Lehrer erklärt in der Schule eine Parabel und sagt: 'Je schärfer die Schenkel, desto höher die Potenz.'"
The joke is based on a wordplay, which is possible in German, but not in English. What is not meant by the teacher (but how pupils can have understood the sentence) is
"A teacher explains in the school a parabola and says: 'The hotter the legs, the higher the potency.'"
The right English translation (which is not funny) would be
"A teacher explains in the school a parabola and says: 'The more sharply curved a parabola is, the higher is the power of its equation'"