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Khan Academy: The Ultimate Free Resource

Updated: Jan 6

What is Khan Academy?

Sal Khan, the founder of Khan Academy, got into teaching by helping out many of his young cousins with their school work. He eventually put his videos online, they became popular, and Khan Academy was born in 2006. Since then, the website has come to span most K-12 topics as well as some collegiate-level courses.

Why Should I Use It?

My favorite part of Khan Academy is that it incorporates many of the best learning strategies: active recall, spaced repetition, self-quizzing, growth mindset, instant feedback, and interleaving.

Even better? You don’t need to know about any of these ideas to take advantage of them.

The best? It’s free! That’s why I consider it the “Ultimate Free Resource” for learning.


In Practice: How to Use It

All material: Practice Questions

Let’s say you’re practicing a question and you get the right answer – that's exciting! Make sure to take a second to look over the Khan Academy solution. Sometimes they will have a more elegant approach, or a different reason for selecting the right answer. This is great way to learn because there may be future problems where the Khan Academy solution is easier or faster.

However, that is not to say the way you got the right answer was wrong. There are always multiple ways to get to the correct answer, so be proud you knew one of them!

Now, let’s say you’re answering a question and you’re not sure of the answer. One of the reasons I love Khan Academy is that there is a “Stuck? Watch a video or get a hint” button at the bottom of the question. The videos help build the content knowledge you need for the question, and the hint guides you to the answer. Remembering what we learned in the active recall article, effort = long-term learning.

As such, I think it is best to watch videos or read articles in the context of a question – and only if you need them! Trying the problem first will always lead to better learning. As discussed in Chapter 4 of Make It Stick by Roediger III, McDaniel, and Brown, even attempting a problem you’ve never been taught how to solve before leads to more learning, as you are better able to retain the answer after trying on your own first.

If you watched the recommended videos and used the hints and you either 1) still don’t understand the solution or 2) roughly understand, but couldn’t explain the solution to a friend, that means more review is needed. Khan Academy will adjust the difficulty of the problems to meet your performance level, which means you can develop your skills at a difficulty tailored to you.

And, of course, these are great problems to bring up with me at our next session!

Finding Material


As your tutor, I am able to assign videos, articles, and practice problems for you to review. This is like homework, and for some students is a helpful way to organize studying. If you have an assignment from me, you can always find it on your dashboard.

Here is a video on how to find an assignment on Khan academy. It is by a teacher made for her class, so after timestamp 1:06 the video becomes more relevant for only her students.

Based on the principle of interleaving, it is best to mix-up your studying. As such, most often I will assign courses or units for you to master – instead of only videos, articles, or practice problems.


As demonstrated in this video, the search function allows you to look up content related to a specific topic. It shows videos, articles, and practice exercises related to the words you type in the search bar.

Like Sal suggests, I recommend using this to get a refresher on a topic or to practice certain problem types. For mastering a topic, I recommend courses and units – discussed next.

Courses & Units

The same video (now linked to a later point) goes over courses and units. These are great for developing mastery in a topic. To start off, you want to learn where you’re at so that you only need to focus on where there are still gaps. For example, if you click on “Geometry,” it will prompt you to take the “course challenge” – also known as the "mastery challenge."

Once you have finished the quiz, on the left-hand side it will show how far away you are from mastering the sub-topics, called units. I have drawn an arrow and boxed where this is on the screen.

NOTE: In the video Sal refers to the unit test as a “mission.” This video is a bit old (2014), and they are now called the “course challenge.

In this case, I did not answer any “Congruence” problems. Let’s say that’s something I feel rusty on, so I could click into that unit to see where I’m at. Once again, I have the opportunity to see what my baseline is for the topic.

I would then take the “Unit Test” at the bottom, and examine my results. This time the performance indicator on the left looks like a tower with a crown (pictured right). As you answer questions correctly, you will move up the tower. To achieve the crown, you’ll need to consistently get 90% of the problems correct.


Looking at your study plan or retrospective study schedule, it may be time to review a course, unit, or lesson (the building blocks of units). The best way is to quiz yourself using either the course mastery challenge, the unit test, the quizzes (usually 1 – 3 per unit), or the practice sets.

In the following pictures I have indicated the practice test button, the quiz button, the unit test button, and the course challenge button.

NOTE: A retrospective study schedule is a great way to use the principle of spaced repetition to decide when to review a topic.

Test Prep: SAT, LSAT, and Praxis Core

As a test prep tutor, one of the challenges is finding good problems to practice with. Why? Only the official material is good enough – because that’s the only material that matches what you’ll see on test day. The downside? Usually official material is expensive.

Khan Academy has teamed up with the College Board for SAT, LSAC for LSAT, and ETS for Praxis Core so that they can offer official material, for free!

Each of these start off with a diagnostic test, which I strongly recommend. With the diagnostic done, you'll have a baseline and know what’s a reasonable target for your test date and the amount of time you can study. Khan Academy also builds in an adjustable study plan for you based on this information.

Using the same process outlined above for questions you know and questions you missed, you will perform better and better as Khan Academy automatically adjusts the difficulty and recommended question topic. That means you won’t have to worry about planning out what topics or what difficulty to study when – Khan Academy has all of that handled.

There are also videos about the tests themselves and recommended test-taking strategies. The latter, because they are only videos without questions, will probably not stick in your brain as easily. So, I suggest using techniques from the active recall article to create question and answer flashcards.

When you miss a question or run out of time, think to yourself, “Is there a test strategy I could have applied here and didn’t? What could help me remember to use that strategy in the future?” And, of course, these are excellent concerns to ask in our next session – or email me about!


Additional Resources

In case you are unsure how to make an account or sign up with the class code I provided, this is a great video. Ignore the instruction to “use your school email.” I recommend using your personal email, or whichever email you check most frequently. Obviously, if your work email does not want you creating accounts with it, please do not use it!