Why do child educators look down upon math and science?

So I am 13, at this assembly in school. This guy dressed as a clown comes in to teach us not to talk to strangers. He had people come up and do activities involving the arts, and the kids liked it. I did not raise my hand as I have always been more of a "nerd", and I have no musical talent with the guitar. I enjoy math, science, and education in general, but it annoyed me when the clown guy said "I'll sing a song about things all kids hate!" Then he started out like BROCCOLLI! SPINACH! CHORES!. But then he started yelling MATH, SCIENCE, SCHOOL, TEACHERS! and things like that. He is assuming that we are all stupid because we are kids, and he is disrespecting the teachers. I know I sound like a suck-up, but he is posing as a role model, yet he tells children at a school that is is right to despise education. The teachers were also enfuriated afterwards, scowling as he preached his biased words of "wisdom". I want to know why.