Add workspace (tex-pad?) to all exercises

[Merbs]

tldr: A instantly parsing textarea. Go to this sandcastle and click on "Show workspace" at the bottom of the page.

This is just a proof of concept as an alternative to the scratchpad. It adds the link "Show workspace" at the bottom of the page alongside "Show scratchpad". When clicked, it produces textarea that takes up half the width of the screen, which upon input, parses that input and displays the parsed tex on the other half of the screen. Atm, it defaults to the pseudo-tex that the expression answer-type reads in and feeds to KAS. It also provides a "Switch to tex" option, which is far less limited, but you need to know tex, and end each line with \\. The provided version has multiline support in the pseudo-tex format (adds the \\ for you). There are definitely issues (for example, KAS can parse 1=1 but can't parse 1=1=1 or 3|x|), but they can be fixed if you (collective) think this is worth pursuing.

As a rationale,

• this is how I do my maths
• an algorithm can possibly read in their input, watch as they reduce line by line, and unobtrusively alert them if they made an error (forgot to distribute a -1, added incorrectly, etc.), with some time delay (or after they submit an answer).
• data aggregation (per problem) could look for common mistakes, which couldn't be derived from the user's guess alone.

[simonjtyler]

I really like this feature, it works well and hope it gets incorporated into Khan Academy. The ideas for how it could be used in the future are interesting; more targeted feedback and hints would be useful on the site.

[Merbs]

@simonjtyler Yay! I'm glad you like it. You should check out Desmos, which I'll be trying to integrate this weekend.

[simonjtyler]

@Merbs I use and encourage students to use Desmos in my classes - it's a really nice graphing calculator webapp, very easy to use. A good challenge is http://dailydesmos.com/

[Merbs]

@simonjtyler @justinj The weekend came early
https://www.dropbox.com/s/4vcv0vz8ispcpha/desmosDemo.mov

[simonjtyler]

@Merbs Nice! It would have to have the option to be enabled/disabled on different exercises. And sometimes I wonder if having easy access to graphing functionality is always a good thing...
But having the option to include desmos in an exercise is a good thing!

[justinj]

@beneater might be interested

[Merbs]

@simonjtyler already in there! On the bottom is the "hide" button next to sratchpad. Also comes with enable/disable functions. It's essentially a carbon-copy of the scratchpad code, except in this commit it was textarea with tex/MathJax and in the new one it's the Desmos API. It's definitely only useful on a subset of the exercises though, and the graphing capability can be disabled/enabled itself (https://www.desmos.com/api/v0.3/docs graphpaper = false;). There are still a few kinks to iron out though.