"Students come to the classroom with preconceptions about how the world works. If their initial understanding is not engaged, they may fail to grasp the new concepts and information that are taught, or they may learn them for purposes of a test but revert to their preconceptions outside the classroom". How People Learn

Examples: Harvard graduates talk about: seasons electricity mass of trees 3:50

"A critical feature of effective teaching is that it elicits from students their preexisting understanding of the subject matter to be taught and provides opportunities to build on—or challenge—the initial understanding."

This is a basic principle from the researh presented in How People Learn

Another Basic Principle from learning research.

Research Based Principle