Founded in 1977, JEI pioneered the concept of "self-learning systems," education plans that enable students to increase their mastery of math and English at an individualized pace. Students from pre-K to 9th grade can take a diagnostic test and have a personalized learning plan drawn up. As they learn, their progress is monitored with interim tests, and before they move up to the next level, an "achievement test" determines which areas they have mastered and which still present problems. Call for more information.