Khan Academy's engaging online video learning covers everything from lessons on mathematics and preparing for standardized tests to mastering personal finance -- all for free.
Focus on STEM subjects: With the US education system's focus on STEM (Science, Technology, Engineering, and Mathematics), Khan Academy's attention to the same subjects across grades and disciplines is a helpful way to enforce at home what goes on in the classroom.
Engaging lessons: The video lessons are short and appealing -- with the narrator drawing on an electronic blackboard to illustrate concepts as he or she speaks. The videos are closed-captioned and come with a transcription and accompanying questions and quizzes to help you practice what you just learned.
Gamified: As you move through lessons and exercises, you can monitor your progress and earn badges, patches, and points to show off to other Khan Academy students.
Learn on the go: Khan Academy has Android and iOS apps that provide a similar learning experience to the browser version, with videos and exercises.
Global reach: Khan Academy also translated lessons into 36 languages, making its world-class learning global.
Focus on STEM subjects: If -- god help you -- you're looking to expand your liberal arts skills, Khan Academy may not be much help. Except for a handful of US, world, and art history courses, Khan Academy puts most of its efforts into math and sciences.
Khan Academy's mission of providing free world-class education is commendable. Its short video lessons are engaging, with lots of incentives to keep moving through a subject. If you're looking to sharpen your skills in math and sciences, Khan Academy has a great selection of topics. Those looking to expand their knowledge of the humanities, however, may need to look elsewhere.