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Math anxiety stems from many places. One of them is the almost unconscious and false idea that mathematics is only worthwhile if the journey of understanding ends with some kind of resolution/solution/success — usually in a time slot of 45 minutes.

Below is a textbook I used around 20 years ago for a HS course here in Ontario. Read the passage about the problems in this section. That message was for students. That message is universal. It applies to every teacher from K to 12.