It is humor probably invented by the students themselves. No one is sneering at anyone. If I called my son's school and got that message I would probably be pressing every button just to see what came next.
Carol - I have met you twice. You are a beautiful sweet woman. Don't be afraid to share yourself with people. Let your defences down. I promise you - no one is ridiculing you. This U-tube addresses a universal problem. Imagine being a teacher and having to deal with a parent who defends their child's right to set fires in the Boy's Room. You either laugh or you cry.

A beloved teacher in my son's school showed up one day with his leg in a cast. His story was that he fell down the stairs. But he confided in me that a student had deliberately tripped him. He protected the student who the teacher felt was not in control when he tripped him. Lots of silly humor about his clumsiness - he was the gym teacher - to get him through the crisis and help the student see the wrong that he had done without harming his status in the school. No one was laughing at the teacher, his clumsiness or his broken leg. Laughter helps to deal with a situation.

I am not preaching, ridiculing, or even advising. It is a shame to me that you don't share yourself with the rest of the community here. If you honestly do not see the humor in that video, fine. But please believe that it in no way is meant to ridicule or hurt anyone. It is ridiuculous and thereby funny.