What are the standards by which authority figures evaluate lower-class youngsters and often pre-judge them negatively?

Middle-Class measuring rods

Explanation:

Authority figures tend to belong to the middle-class, and some of them, to the upper class.

Middle-class measuring rods refer to the standards, mannerisms, styles, clothes, vocabulary, way of speaking, and other things associated with the middle-class.

Because lower-class youngsters rarely can live up to those expectations (for the mere reason that they are lower-class, not middle class, and lack the economic means), they are often, either subconsciously or consciously, judged more harshly by their authority figures than their middle-class and upper-class peers.