Khan Academy made mastery learning free, and proved 11 weekly minutes move math scores

Khan Academy began in 2008 when Salman Khan started posting video lessons; it became a nonprofit with the mission of providing a free, world-class education to anyone, anywhere.

Its mechanism is mastery learning delivered by software: short videos explain a topic, exercises give immediate feedback, and students only move on once they have mastered the skill. This lets every learner move at their own pace — something a single teacher with 30 students cannot do.

The effect is measurable. A January 2026 PNAS study using three years of administrative data on over 200,000 students found that even 6.6 hours of Khan Academy practice a year (about 11 minutes a week) produced a 0.031 standard-deviation gain in math scores, with gains scaling to 0.085 SD at 30 minutes a week.

Gate progress on demonstrated mastery

Instant feedback beats homework that is graded days later.

Mastery gates stop students from piling up gaps they can never close.

Software costs a fraction of tutoring and reaches any device.

The data lets teachers see exactly which skills each student lacks.

Scale the tutor, not the classroom: instant feedback plus a mastery gate delivers measurable learning at a fraction of the cost of human tutoring.

By the 2024-25 school year Khan Academy reported 227 million registered users, 104.9 million learners that year and availability in 55+ languages across 190+ countries; districts now license its accelerator programs, which is how the PNAS study's data was generated.