There were two motivations why I wrote this article:

- Recently I have undertaken coaching mathematics, physics and computer science.
- I saw an interesting video¹ from the mistakes of mathematics education, and the lecturer outlined a better teaching method.

In this way I have recurrently getting a lot of experience about how bad methodology is used in mathematics education not only here in Hungary, but everywhere in the world.

But let us take some examples from my own experience:

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