Bell Lancaster Method

The Bell-Lancaster method (also known as "mutual instruction" or the "monitorial system"), named after the British educators Dr Andrew Bell and Joseph Lancaster who both independently developed it, was an education method that became popular at a global scale during the early 19th century. The method was based on the abler pupils being used as "helpers" to the teacher, passing on the information they had learned to other students. The Bell-Lancaster method was found very useful by 19th-century educators, as it proved to be a cheap way of making primary education more inclusive, thus making it possible to increase the average Class Size.

http://en.wikipedia.org/wiki/Bell-Lancaster_method