In traditional teaching, formal principles (laws, formula, problem solving procedures) in mathematics and science are often taught abstractly and then illustrated by an example.
The method has been developed and explored at the University of Bergen, and was called for by John Dewey in his 1899 book The School and Society.
With new technologies, teachers and students can help build a database of examples that users can retrieve when the formal principle has to be learned.
After the solution attempt, the principle behind the joint probability of two independent events will be explained, using the chosen example.
[1] One study by Perkins, Gratny, Adams, Finkelstein, and Wieman found that interest in physics declined during a semester-long introductory calculus-based mechanics course.