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Hobby programmers are making a big difference right now, helping out Khan Academy by contributing exercises.

The whole thing is open source: http://github.com/khan/khan-exercises

We've had people who claim to have never been professional programmers come in and create impressive exercises that thousands of students are using daily to fill gaps in algebra, trig, calculus, etc.

Sweet. Does the Khan Academy plan to incorporate interactive simulations into its curriculum? I'd imagine they'd be very valuable in fields like physics, where concepts aren't particularly transparent unless you get to play with them for a while.

Here's a couple examples of the sort of thing I mean. Along with another physicist, we've made a complete special relativity simulator (still rather beta, though -- UI needs improvement, and the demos don't have much explanation):

http://schroedingers-hat.github.com/jsphys/relativity/relati...

There's some premade demos, and the goal is to make it embeddable so it can be used along with a video or text to illustrate a point. I've also done a bit of an interactive tutorial on wave interference, where you can play with waves to see the result:

http://schroedingers-hat.github.com/jsphys/waves/wave_summat...

Eventually I'd like to finish off these simulations and use them to teach, as part of a complete curriculum. There's been some past efforts (with Java applets, for instance), but nothing integrated into a curriculum. Someday...

Yes yes yes. We're:

A) taking small steps every day to make our exercises more and more interactive (see @jpulgarin's link below)

B) thinking about longer-term projects, simulations, whatever you want to call 'em.

We welcome anybody to step in and blow the doors off our current exercise framework with a full-fledged simulation of some sort.

For example: http://www.khanacademy.org/exercises?exid=derivative_intuiti...

That's brilliant. I may need to start recommending these to my students.

I'm student teaching in a high school classroom right now while trying to complete my BS in Math and get my initial teaching license. There is a growing trend in the classroom to allow students to move on even when they have no foundational skills. As long as they get a D they get credit and can move on regardless of their lack of a solid foundation from which to accurately build upon.

A large part of the issue is that the classrooms aren't differentiated by ability so we have students who can't really do or understand basic math but we're trying to teach them algebra and trigonometry. Some of them may pull through but do they really understand the subject matter when they don't understand the foundation from which it builds upon?

One of my education instructors told me once that it doesn't matter if a student can calculate 20x15 as long as they understand that we're looking for a number that is 20 times larger than 15. The problem is they really don't understand and they must rely on a calculator for even basic math. It really is disappointing and I'm not sure I want to teach anymore.

I feel like the system is broken and just because someone, somewhere said that when we educate students like this they can perform just as well or better than if we actually made sure they were in a class that suits their abilities we've latched onto it as a method of reform.

(I taught developmental math for 2 years at a local community college. My classes were difficult and I expected a lot of my students but the instructors that ended up with my students later on were all grateful of the foundation that I made sure my students had.)

This is why I'm excited about methods like the Khan Academy's exercise system, where you're encouraged to stay on a concept until you truly understand it.

As other replies you have received have mentioned, Khan Academy is working hard at improving its exercises in that regard. An even better current example, a service that costs money (except for UNLIMITED short-duration free trials) is ALEKS

http://www.aleks.com/

which my wife and I are using to learn accounting and all four of our children have used or are using to learn mathematics and chemistry. ALEKS is a very useful tool for beginning college students who have gaps in their knowledge, which is most college students. See

http://www.aleks.com/about_aleks/Science_Behind_ALEKS.pdf

for a detailed explanation of the "knowledge spaces" theory behind ALEKS.

As a user of Aleks can you describe what makes it better than the Khan Academy?

As a user of Aleks can you describe what makes it better than the Khan Academy?

Thanks for asking the useful follow-up question, which I upvoted to encourage that kind of behavior here in what is meant to be an informative online community.

My experience as an actual, PERSONAL user of ALEKS only began yesterday, when my wife (the registered user) started taking the accounting course, with me second-chairing as we discuss the exercises together. But all of my children have used ALEKS

http://www.aleks.com/

for a while, so I will discuss its strengths in relation to Khan Academy

http://www.khanacademy.org/

and in relation to the Art of Problem Solving (AoPS),

https://www.artofproblemsolving.com/

another Web resource that all HN participants ought to know about. The strength of ALEKS is its thorough research base on curriculum topic interconnections based on the "knowledge spaces" theory

http://www.aleks.com/about_aleks/Science_Behind_ALEKS.pdf

that gives the ALEKS program its name. The online assessment that begins each ALEKS course identifies exactly what each learner already knows (in the scope of the syllabus of an ALEKS course) and suggests next topics to cover based on just what will broaden the learner's knowledge base enough to link to new unlearned topics that the learner can learn after first learning the current unlearned topics. ALEKS uses adaptive, periodic assessments to keep a learner in his or her "zone of proximal development," to use a term from another learning theorist, and is relentless in checking for gaps in knowledge or previous topics that the learner has forgotten. For my oldest son, who got past the top level of the ALEKS curriculum years ago, the ALEKS courses were perfect for spot review of a course (for example, high school algebra 2) just before a semester final in the distinct, accelerated mathematics course he was in at the time.

http://www.mathcep.umn.edu/umtymp/

For my younger children, ALEKS is less repetitive than the courses at the local high school that my second son tried out for a while (we are mostly homeschoolers) and very accommodating of the radical acceleration (precalculus topics at sixth grade age) that my third son is now pursuing in math studies to support his interest in science. The advantages ALEKS has over Khan Academy include more open-ended online problems, very careful research on interrelationships of topics based on knowledge spaces theory, thorough and complete syllabuses for each course based on international best practice, and smooth transition from one level of the ALEKS program to the next. ALEKS has a moderate list price (with discounts for longer enrollment terms or multiple enrollments from the same family, and UNLIMITED free trials). The cumulative progress information available to learners who pay the moderate price for ALEKS is quite useful and increasingly familiar to schools.

Advantages that Khan Academy has are low list price (free), a syllabus that goes up to higher-level topics than ALEKS (multivariable calculus and linear algebra, with the sky the limit for future courses), and the engaging online videos. We are still light users of Khan Academy in our household, but precisely because several HN participants are improving the Khan Academy exercise engines, I will encourage my children to use Khan Academy more and more over the next few years, and I could use it myself to learn math beyond precalculus.

The Art of Problem Solving (AoPS) is an online community I have participated in for years. (My screen name originated there.) The free program Alcumus there

https://www.artofproblemsolving.com/index.php?mode=interacti...

illustrates some ways that other online programs could serve up problems rather than mere exercises. The online community there supports some extremely interesting online classes that get into MUCH harder problems than those served up by Khan Academy.

Does this answer your question? Thanks for asking for more details.

I don't know whether it answered his questions, but allow me to thank YOU for providing so many useful details. So often, it seems, I'll stumble across a fascinating post on the topic of K-12 education, and I'll find your screen name at the top. If you have a blog, post a link; if not...(hint, hint).