Mathematics teachers should understand the following basic facts
If X doesn't want to be found, respect it's privacy until it has violated the laws of the land. Don't teach children to stalk by repeatedly asking them to find X
Don't teach children to borrow at an young age itself
Steps are not always, everyone has a shortcut on their desktops
Nobody builds a wall with 10 people and later build one more to find out how many days it will take.
A person who tries to fill a water tank at one end and keeps emptying it at the other has a psychological problem. His madness should not be posed as a problem to students
There are easier ways to find the diameter of a circle than through complicated formulaes