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So maybe KA is actually ASSUMING that they don’t have the ability to create the best learning experiences, and therefore that they should focus now on building the infrastructure to allow everyone else to make content and upload it so it can be tested.

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I say this as a teacher who stopped using KA last year because it was too hard for students to earn proficiencies. But I think KA is working on lots of these problems, and those infrastructure problems are frankly bigger than the issues with decimals or other content areas, because without better infrastructure, you still wouldn’t be able to do much even with better content.

Now can we do something about the decimals up in there?

See, Ben writes that going either into new exercises that we’re creating or into existing exercises that we’re improving and that Sal is currently making new videos which complement all of our new exercises, so that we can ensure that Sal is explaining the same concepts that the standards cover.

In some content areas, the foundation of this process is broken. Dan got one of them fixed through the conversation here. Would Khan Academy consider working on decimals next? By the video Sal Khan made the other day, it seems you have been working on them quite recently. Let’s get it right while you’re there.

The expression problems are ok. Especially like: __ ( __ x + 7q) is equivalent to 10x + 14q.

The function questions need a lot of editing. What is the end behavior for i) energy stored in a spring as a function of displacement ii) water left in a draining bucket as a function of time iii) force needed to keep an object on a carousel as a function of rotation speed (correct answer — as carousel rotates faster & faster there is no LIMIT to the amount of force needed). Yikes!

The “fix” to the box plot problem makes the problem even more procedural. Students now have to deal with a technicality for defining quartiles that really is not very important.

Every concept has to have a beginning. This coming year, that activity won’t be the first exposure to box-and-whisker plots for my students. It also won’t be the last. It does, however, provide a very good structured practice for creating box-and-whisker plots which doesn’t rely on a student being able hold a ruler and draw perfect lines. It also provides the instant feedback of “I got this correct” or “I need to try something else” which I cannot provide immediately to 20+ students at the same time.

Will I go on to teach students how to compare different data sets? Of course I will. Will I find real world examples of these graphs in scientific or medical literature and have students analyze them? Yes. Will I rely on Khan Academy to teach my students everything? Of course not.

I’m not a KA fanboy. I don’t sign my students up each year and require them to complete X activities each week, etc. I do, however, direct students to specific videos occasionally or ask them to try out certain activities. KA can be a useful tool. In this case, while there is room for improvement, the KA box-and-whisker tool is far more versatile and clean-looking than the one I’ve been using on NLVM. It is excellent for BEGINNER practice on identifying landmarks in a set of data and locating how they fit onto a Box Plot. I intend to use it as a small group station activity while I run a more engaging small group activity that approaches this from a different angle. For that, there is absolutely nothing wrong with it. As with everything, it’s all in how it’s used.

However, Ben explains that they “haven’t included outliers in the exercise because there exists a variety of different ways to draw box plots.”

I am not directing this to Ben particularly, but isn’t the real point of teaching box plots so that students can *read* them? And aren’t they going to have to read all the varieties in use? Drawing box plots by hand is not a CC standard, and drawing them using the Khan Academy widget is not something they will ever see again. But someone came up with a way to simulate drawing box plots with no outliers, so now it’s part of the program and teachers are going to have to teach students how to follow the steps to draw a box plot.

This is at the expense of spending time on what the consensus of math teachers on this page seems to think is important: interpreting and comparing box plots of real-world data. Presumably, from real sources with slightly different formatting standards. Because the standard doesn’t mention outliers specifically or comparing two box plots, does that mean that Khan Academy or anybody else aiming for CCSS alignment is going to skip those things? Isn’t this the kind of shallow, broad “coverage” approach with lots of rules that we are supposedly leaving behind? Why are the mechanics of sorting numbers and calculating medians being taught, drilled and tested under the name of box plots instead of the real thing? Since box plots are the only part of the 6th grade standards that prompt a discussion of what an outlier is and a precise definition, it’s not something to gloss over lightly.

Again, I don’t mean to pick on Ben and Khan too specifically–I worked with a 7th grade textbook that took the same approach, and I know they’re working from what the current texts do. I think the box plot page is going to be the page I check out first from now on when I’m trying to get a feel for a new math text!

All these new problems are going either into new exercises that we’re creating or into existing exercises that we’re improving. Here are a few examples of the new exercises:

Writing numerical inequalities
Equivalent expressions
Interpreting features of functions

So far we’ve added around 50 new exercises like this and are adding more every week. We’re working through each of the CC standards to make sure that we cover them accurately — so far we’ve created exercises for the major clusters (defined here) in the 6th grade standards. We’re quickly working to cover the major clusters for other grades and then the remaining standards after that.

As I mentioned on Twitter, we feel that the CC standards are excellent, primarily due to their focus on conceptual understanding over rote memorization. We’re in talks with Student Achievement Partners (creators of CC) to have them review our content to make sure that it matches their original intent.

Finally, Sal is currently making new videos which complement all of our new exercises, so that we can ensure that Sal is explaining the same concepts that the standards cover.

Hope that gives you an idea.

In the last few months, we’ve hired many seasoned content creators to work with us on covering all of the the Common Core standards accurately. So far, they’ve created thousands of new handwritten questions that focus more on conceptual understanding to complement the machine-generated exercises we already have.

Can you tell us how this team of content experts helps improve the videos and exercises on Khan Academy, given that those comprise a student’s primary experience with Khan Academy?

https://www.khanacademy.org/math/probability/descriptive-statistics/Box-and-whisker%20plots/e/creating_box_and_whisker_plots

Dan, thanks for pointing out that this exercise wasn’t what it could be — your feedback here is valuable.

I’ve updated the exercise so that it now includes anywhere from 8 to 15 points, so students are forced to deal with two middle numbers, both in finding the median and in finding the quartiles.

Michael, thanks for your feedback about the user interface. I’ve improved it so that when dragging a point, any other points that are “in the way” will shift over such that it isn’t necessary to drag the points in any particular order.

Both changes are now visible when you visit the exercise:

https://www.khanacademy.org/exercise/creating_box_and_whisker_plots

Brian’s comment about the Common Core standards mentioning only the construction of box plots is astute — if we go a step further and look at the 6-8 Statistics and Probability CC progression doc (available at http://commoncoretools.me/wp-content/uploads/2011/12/ccss_progression_sp_68_2011_12_26_bis.pdf) then we find that the authors of the standards in fact also recommend that in 6th grade, students are able to compare two distributions by using box plots. I agree that comparing box plots is much more valuable, so in the future, we’ll likely add an exercise for comparing plots.

We haven’t included outliers in the exercise because there exists a variety of different ways to draw box plots. Indeed, the progressions doc linked above says, “Because of the different methods for computing quartiles and other different conventions, there are different kinds of box plots in use. Box plots created from the five-number summary do not show points detached from the remainder of the diagram.” With this exercise, we’ve intentionally chosen to provide random numbers generated from a normal distribution so that students can focus on the important parts of a box plot and don’t need to worry about the differing ways to plot outliers.

In the last few months, we’ve hired many seasoned content creators to work with us on covering all of the the Common Core standards accurately. So far, they’ve created thousands of new handwritten questions that focus more on conceptual understanding to complement the machine-generated exercises we already have.

https://www.khanacademy.org/about/our-content-specialists

Finally, I just want to mention again that our exercise framework is open-source and we’re open to contributions; please submit a pull request at https://github.com/Khan/khan-exercises if you find more possible improvements to our exercises — I’ll be happy to take a look at your change.

Ben