This is what kids learn in their preschool years and the first three years of primary school.

Here’s how I would organize these 57 courses into 15 topic areas by consolidating courses that cover similar topics: The World of Math mission draws from many of the 57 courses, but it picks a subset of the exercises to avoid duplication.

For example, the Differential Calculus, AP®︎ Calculus AB, and Calculus 1 courses each work as a first course in Calculus. Khan Academy currently offers 57 math courses, but many topics are covered by multiple courses. Since I’m writing about curriculum this week, I’ll use the new system’s course-based structure. But this flat structure makes it harder to see how problems fit into the overall math curriculum. You don’t have to worry about which subjects the problems come from. I find the World of Math system simpler to navigate: you can just keep clicking the “Start mastery challenge” button, and problems keep appearing. So if you use one system for practice, you get credit in the other system and don’t have to review topics you already know. Fortunately, the two systems share mastery status for each skill. The previous World of Math system coexists with a new mastery system based on courses. Khan Academy is in the middle of a mastery system upgrade. Next week, I’ll look at how they relate to discrete math topics. This week, I’ll go over the topics available on Khan Academy. These gaps can slow down further learning, since math success in later courses depends on knowing the skills taught in previous courses. The idea is to fill in “ swiss cheese gaps” in knowledge that often accumulate when learning math in school. But Khan Academy can also help adults review the fundamental skills necessary to learn more advanced math.

These skills map to school curricula like the US Common Core, so that when students learn something on the site, it translates to success in the classroom. Khan Academy’s math program is designed to help children and young adults learn and practice a particular set of math skills.

Khan linear algebra