So they can open doors of opportunity for their students.
Because they don't like random people knocking on their doors
Bolzano the door!
Some sort of karate expert I can't even open a Cheetos bag.
Gloves. Just kidding, he hasn't opened it yet.
A student used to give his teacher some raisins everyday. He kept giving them for 3 months straight. Then one day he did not give raisins to his teacher. And his teacher asked him "Where are the raisins today?", and the boy said "My rabbit died."
Math teachers, because every student counts.
Student: A teacher!
Because he is forever a loan.
That is impossible. Opportunity doesn’t come knocking twice!