For example, the school requires them to keep their notebooks in class rather than take them home where they could be forgotten.

We all know the standard drill for a math class. The teacher delivers lectures on a new concept, students do some homework problems, and after a few weeks they take an exam.

For nearly 20 years, high school chemistry teacher Jonathan Bergmann would teach a lesson in class, help students after school and give them standard homework assignments. He was good enough to ...