Our schools should not be teaching our children what not to think either. That is actually the same as teaching them what to think. Our schools should only be teaching our children HOW to think. Anything beyond that is reserved to the parents. In places like Communist China, North Korea, Cuba, and Venezuela, it is mandated to teach children what to think and what not to think. We don't want that here in the USA.
Although my handle, Twinbrains, makes it appear that I could be a mathematical genius, I can assure you that I am not. However, somewhere during my years of education, I learned how to calculate that 2+2=4. During that education, my learned teachers did not teach me all the specific and infinite number of answers that 2+2 does not equal to, such as; 2+2=5, 2+2=73, 2+2=cow. Instead of teaching me what not to think, my teachers taught me how to think and how to calculate the correct arithmetic answer, which I believe is 4.