Procrustean

What teachers shoudn´t be: 

treating all people the or things as if they are the same, without considering individual differences and in any way that is too strict and unreasonable. 

Producing or designed to produce strict conformity by ruthless or arbitrary means.

(Literary & Literary Critical Terms) tending or designed to produce conformity by violent or ruthless methods]

Adj.

1.

Procrustean - of or relating to the mythical giant Procrustes or the mode of torture practiced by him

Origin: from the Greek story of Procrustes, a robber who forced people to lie on a bed and made them fit it by stretching their bodies or cutting off part of their legs.