# Klassenzimmer 2023

This is a movie in German. The translation is "The teacher's lounge". Carla Nowak is an enthusiastic initiative math teacher. She asks the class in a "warm-up" exercise, whether 0.9999999.... is equal to 1 or not. This is a classic question which most students without exposure to calculus and answer wrong. I tried it out in a calculus class and got more than a 5:1 ratio claiming that 0.999999 ... is smaller than 1, and that is at Harvard. That somebody in middle school can even give a proof (one of the kids presents a proof on the board 1/9 = 0.111111, so that 9/9=0.9999999 but 9/9 is also 1), is a rather hard to believe. I find this rather unrealistic. There is a Piaget type transition which must happen until a student understands that there is no difference between 0.99999.... and 1. But the movie is very valuable and points the finger on a major issue we face in education. You have to watch the movie yourself to find out.

MOV, Ogg Webm. IMDB link
Oliver Knill, Posted January 29, 2024,