
Khan Academy Triples Unique Users To 3.5 Million - ssclafani
http://techcrunch.com/2011/10/19/khan-academy-triples-unique-users-to-3-5-million/
======
michaelchisari
Count me as one of those recent sign-ups. I've been doing Khan Academy
religiously for the past month, and have gotten up to 800,000 points and
185/211 exercises. The practice board is addicting and fun, and reminds me in
ways of role playing games (like Final Fantasy XI's "License Board"), which
I've always been a fan of. After I finish, I plan on moving on to the MIT OCW
math classes.

I can't imagine how much easier K-12 would have been had Khan Academy been
around. I've looked at other math and learning resources, and while they're
all solid in ways, there just seems to be something that Khan "gets" that
others don't, even if it's just as simple as a good UI and design.

In my opinion, Khan Academy is worth every ounce of hype, and I'm usually
someone who is strongly anti-hype.

~~~
mrchess
This is gonna sound stupid but I'm serious. Did you learn anything worthwhile
from your investment? Any new useful "skill" or all just top level knowledge?
Do you consider materials learned from Khan life changing?

~~~
0x12
Why would it have to be life changing in order to be useful?

The trade-off could well be watching soaps vs re-doing your high school or
university level math.

~~~
mrchess
I meant useful or lifechanging as two seperate questions -- no correlation.

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0x12
I love the Khan academy, it is one of the best things that came out of the
internet to date.

But I really wished that they would allow me to sign up with them and them
alone without having to use either google or facebook to log in, that's a
really bad mistake on their part imo.

~~~
tptacek
Why? Things seem to be going well for them (look at the article you're
commenting on). There are smart web people building this system up; presumably
this is something they thought hard about before implementing.

~~~
0x12

      - facebook and/or google may not be around forever
    
      - my account with facebook and/or google could get disabled by them on a whim, 
        severing my link with the Khan academy
    
      - there is no upside to me to log in with a facebook
        and/or google account
    
      - there is a downside, which is that I have to sign up for a different service, that
        I may have valid reasons for not wanting to join (in the case of fb that does not
        require a whole lot of imagination)
    

And so on.

Really, when you only allow people to log in to your site by forcing them to
become a member of another site first you are creating a barrier that need not
exist.

I'm sure there are plenty of valid reasons for them why they do it this way
(possibly, for instance because google and facebook do a lot of work to ensure
that their accounts are only given out to those that deserve it, thereby
cutting out on spam), but for _me_ it does not work.

For sure that is a small minorities, but small minorities are at least still
allowed to speak up. Good thing HN does not require a facebook or a google
login.

~~~
casenelson
This is also a problem for some school boards. My sister is using Khan Academy
with her ELL students (they don't speak any English but Khan's working great
for them).

Signing a student up to a standalone service is no problem, but as soon as
that service includes email or other student communication, the teachers need
to get parents' consent.

This is really limiting the adoption across the rest of her school, they don't
really want to get everyone a new GMail or Facebook account.

~~~
kamens
We're aware of this, and as @genieyclo said, Google Apps for Education is
currently the easiest way for a whole bunch of students to get going. We've
been successful using Apps for Education with all of our pilot Khan Academy
schools so far.

That being said, we're thinking about becoming our own identity provider as
well, primarily for this reason.

Just one of those things that's on the list and has to be weighed against
everything else -- the majority of our users are doing just fine w/
Google/Facebook.

~~~
0x12
Super, great to see it's on your radar. Thank you very much for all your hard
work.

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vasco
Isn't it required to be at least 13 years old to have a google account? How
does this affect the kids who want to use khanacademy? Are they forced to have
a facebook account?

EDIT: Actually, facebook also has a minimum age requirement of 13
(<https://www.facebook.com/help/?faq=210644045634222>). Can't see how
khanacademy missed that. I think this is a major flaw in their signup system.
Should they (khanacademy) really be blocking every kid younger then 13?

EDIT2: It seems like they address it here
(<http://www.khanacademy.org/about/getting-started>) but their solution is
having the parents create an account for the kids.

I don't really think this is actually acceptable by facebook's terms of
service though, not sure about google. See point 4 in
<https://www.facebook.com/terms.php>

~~~
corysama
From <http://www.khanacademy.org/about/getting-started>

\-----------------------

If your students are under 13:

You currently have two options: you can sign your school up for Google Apps
for Education, which will help you provide each student with a Google account
that can be used with Khan Academy, or you can have your students' parents
individually create accounts for each student on either Google or Facebook. We
are constantly working to improve this situation, but that's the best we've
got at the moment (sorry!).

If you already have Google Apps for Education accounts but aren't able to use
them to sign in on the Khan Academy, you might need to upgrade your account.

~~~
vasco
That's only for people with Google Apps for Education (teachers)!! Also, if
you are under 13 you can't use the site if you didn't sign up with
google/facebook (which have their own weird under 13 rules)

See "1. Eligibility" in (<http://www.khanacademy.org/about/tos>)

EDIT: Also, I found out that youtube actually doesn't let anyone under 13 use
their service, so I'm guessing you can't watch the videos either if you're
under 13. See "12. Ability to Accept Terms of Service" in
([http://www.youtube.com/static?gl=US&template=terms](http://www.youtube.com/static?gl=US&template=terms))

I just found out the internet is just for people over 13...

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hugh3
I hadn't looked at Khan Academy in a year or so, but it looks like they've
vastly expanded their offerings since then. In particular, they've added a
couple of hundred lessons of Art History stuff, which I'm quite keen to look
through.

The mathematics and physics stuff would have been great for me... if it had
existed fifteen years ago.

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nickik
I think it would be nice if MIT (and others) would make a deal with the
khanacadamy to provide there courses in a khanvideo style and change there
exercises in khan-style exercises. Everbody on the World should be able to
learn anything from 1+1 to quantum physics on khanacadamy.

OCW kind of stuff is already super awesome but in would be much better in a
khan-style. When you watch lectures on OCW you know its not for you, its for
the studens in the class. The professor talks about when the exams are and so
on. The other thing is that its hard to know when you are ready to take a
course, in the khan system you could show what you have to know to do the
course.

I see a bright future for education.

~~~
tokenadult
_change there exercises in khan-style exercises_

It would be a disaster for MIT's education if the legendary MIT problem sets
were turned into Khan Academy-style exercises. To explain why I think so,
allow me to quote the FAQ I prepare about the distinction between "problems"
and "exercises" in mathematics instruction for families of students in the
math classes I teach:

PROBLEMS VERSUS EXERCISES

I frequently encounter discussions among parents about repetitive school math
lessons, so a few years ago I prepared this Frequently Asked Question (FAQ)
document about the distinction between math exercises (good in sufficient but
not excessive amount) and math problems (always good in any amount).

Most books about mathematics have what are called "exercises" in them,
questions that prompt a learner to practice the concepts discussed in the
mathematics book. By reading one mathematics book, and then several more, I
learned that some mathematicians draw a distinction between "exercises" and
"problems" (which is the terminology generally used by the mathematicians who
draw this distinction). I think this distinction is useful for teachers and
learners to consider while selecting materials for studying mathematics, so
I'll share the quotations from which I learned this distinction here. I first
read about the distinction between exercises and problems in a Taiwan reprint
of a book by Howard Eves.

"It is perhaps pertinent to make a comment or two here about the problems of
the text. There is a distinction between what may be called a PROBLEM and what
may be considered an EXERCISE. The latter serves to drill a student in some
technique or procedure, and requires little, if any, original thought. Thus,
after a student beginning algebra has encountered the quadratic formula, he
should undoubtedly be given a set of exercises in the form of specific
quadratic equations to be solved by the newly acquired tool. The working of
these exercises will help clinch his grasp of the formula and will assure his
ability to use the formula. An exercise, then, can always be done with
reasonable dispatch and with a minimum of creative thinking. In contrast to an
exercise, a problem, if it is a good one for its level, should require thought
on the part of the student. The student must devise strategic attacks, some of
which may fail, others of which may partially or completely carry him through.
He may need to look up some procedure or some associated material in texts, so
that he can push his plan through. Having successfully solved a problem, the
student should consider it to see if he can devise a different and perhaps
better solution. He should look for further deductions, generalizations,
applications, and allied results. In short, he should live with the thing for
a time, and examine it carefully in all lights. To be suitable, a problem must
be such that the student cannot solve it immediately. One does not complain
about a problem being too difficult, but rather too easy.

"It is impossible to overstate the importance of problems in mathematics. It
is by means of problems that mathematics develops and actually lifts itself by
its own bootstraps. Every research article, every doctoral thesis, every new
discovery in mathematics, results from an attempt to solve some problem. The
posing of appropriate problems, then, appears to be a very suitable way to
introduce the student to mathematical research. And it is worth noting, the
more problems one plays with, the more problems one may be able to pose on
one's own. The ability to propose significant problems is one requirement to
be a creative mathematician."

Eves, Howard (1963). A Survey of Geometry volume 1. Boston: Allyn and Bacon,
page ix.

I have since read about this distinction in several other books.

"Before going any further, let's digress a minute to discuss different levels
of problems that might appear in a book about mathematics:

Level 1. Given an explicit object x and an explicit property P(x), prove that
P(x) is true. . . .

Level 2. Given an explicit set X and an explicit property P(x), prove that
P(x) is true for FOR ALL x [existing in] X. . . .

Level 3. Given an explicit set X and an explicit property P(x), prove OR
DISPROVE that P(x) is true for for all x [existing in] X. . . .

Level 4. Given an explicit set X and an explicit property P(x), find a
NECESSARY AND SUFFICIENT CONDITION Q(x) that P(x) is true. . . .

Level 5. Given an explicit set X, find an INTERESTING PROPERTY P(x) of its
elements. Now we're in the scary domain of pure research, where students might
think that total chaos reigns. This is real mathematics. Authors of textbooks
rarely dare to pose level 5 problems."

Graham, Ronald, Knuth, Donald, and Patashnik, Oren (1994). Concrete
Mathematics Second Edition. Boston: Addison-Wesley, pages 72-73.

This digression becomes the subject of a, um, problem in Exercise 4 of Chapter
3: "The text describes problems at levels 1 through 5. What is a level 0
problem? (This, by the way, is NOT a level 0 problem.)"

"First, what is a PROBLEM? We distinguish between PROBLEMS and EXERCISES. An
exercise is a question that you know how to resolve immediately. Whether you
get it right or not depends on how expertly you apply specific techniques, but
you don't need to puzzle out what techniques to use. In contrast, a problem
demands much thought and resourcefulness before the right approach is found. .
. .

"A good problem is mysterious and interesting. It is mysterious, because at
first you don't know how to solve it. If it is not interesting, you won't
think about it much. If it is interesting, though, you will want to put a lot
of time and effort into understanding it."

Zeitz, Paul (1999). The Art and Craft of Problem Solving. New York: Wiley,
pages 3 and 4.

". . . . As Paul Halmos said, 'Problems are the heart of mathematics,' so we
should 'emphasize them more and more in the classroom, in seminars, and in the
books and articles we write, to train our students to be better problem-posers
and problem-solvers than we are.'

"The problems we have selected are definitely not exercises. Our definition of
an exercise is that you look at it and know immediately how to complete it. It
is just a question of doing the work, whereas by a problem, we mean a more
intricate question for which at first one has probably no clue to how to
approach it, but by perseverance and inspired effort one can transform it into
a sequence of exercises."

Andreescu, Titu & Gelca, Razvan (2000), Mathematical Olympiad Challenges.
Boston: Birkhäuser, page xiii.

"It is easier to advance in one topic by going ahead with the more elementary
parts of another topic, where the first one is applied. The brain much prefers
to work that way, rather than to concentrate on ugly technical formulas which
are obviously unrelated to anything except artificial drilling. Of course,
some rote drilling is necessary. The problem is how to strike a balance."

Lang, Serge (1988), Basic Mathematics. New York: Springer-Verlag, p. xi.

"Learn by Solving Problems

"We believe that the best way to learn mathematics is by solving problems.
Lots and lots of problems. In fact, we believe the best way to learn
mathematics is to try to solve problems that you don't know how to do. When
you discover something on your own, you'll understand it much better than if
someone just tells it to you.

. . . .

"If you find the problems are too easy, this means you should try harder
problems. Nobody learns very much by solving problems that are too easy for
them."

Rusczyk, Richard (2007). Introduction to Algebra. Alpine, CA: AoPS
Incorporated, p. iii.

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sosuke
I'm loving Khan Academy since I saw a post by John Resig about their practice
framework. Math is so much more fun and interesting since I started using Khan
Academy.

~~~
kiba
Unless you practice your mathematics and physics daily, you will eventually
forget most of what you know.

~~~
gwern
Yes, but hopefully KA will get its spaced repetition (
<http://www.gwern.net/Spaced%20repetition> ) efforts going at some point,
while most users are still there.

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graeme
I teach the SAT, and I have all of my students do the arithmetic exercises on
Khan academy + the exercises for any subjects they have difficulty with.

It works great. Students nowadays tend to do all of their math on a
calculator; they're not so great at mental math. It really holds them back on
the SAT. The test's format invites calculation errors. The SAT specific videos
are great, too.

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gghootch
1\. I wonder what their international user base looks like. (Not counting
native English speaking countries like UK & India)

Two weeks ago my mom cut out a lengthy article for me, as she often does when
she thinks she's read something relevant to my interests. To my surprise it
was on Khan Academy, something I already read about past summer in Wired.

2\. Does anyone know whether KA has received any more international press
coverage lately?

~~~
bantic
KA plus One Laptop per Child would be an incredibly powerful combination for
third-world schools. OLPC should make it the homepage on the XO.

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rubergly
In case anyone is wondering, Khan Academy did not launch today, as CrunchBase
seems to think.

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pixcavator
I'd be much more impressed it these (or at least a part of them) were paying
customers.

~~~
solutionyogi
Why? Khan Academy is a non profit organization. They are not looking to make
money. They are trying to change the world of education.

I am impressed by these numbers because it means that more people are now
aware that there is a quality free resource where they can educate themselves.

~~~
pixcavator
Why would it be more impressive? Because paying customers vote with their
money. Money is a better validation than "you're great!".

~~~
solutionyogi
Yes, money is a validation if your goal is to make money. If I am a for-profit
company and I show you millions of visitors for my website but no real
revenues, I would agree that it's not impressive.

As the other commentator pointed out, their goal is not to make money. And
this is impressive because it's a huge progress towards their stated goal.

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dbbo
I found some of Khan's orgo videos helpful review material. In fact, the
doctorate-level professor I had didn't do a much better job (if at all better)
of explaining the material the first time around.

