The Kumon Philosophy

Kumon is a math and reading enrichment program. Students do not work together as a class, but progress through the curriculum at their own pace, moving on to the next level when they have achieved mastery of the previous level. Students are often guided by tutors to develop their mathematical and reasoning skills. Mastery is defined as speed (using a standard completion time) and accuracy. They take an achievement test at the end of each level. - Wikipedia.