[hsparikh]

We are wholly inspired by Bret's work, and are currently playing around with the tangle library to help students visualize the concept of area, perimeter, and volume. Here is a preview: http://tuvalabs.com/resources/area/

We also plan to open source this code in due time. Ignore the mess please.

[bajsejohannes]

A suggestion for the visual area widget: Count the boxes for the user. So in the first box you'd write 1, the second 2, etc. Then it's easy to verify that the numbers are indeed a counting (they increase by 1) and that the calculated are indeed checks out.

I'd write the numbers in gray so they don't dominate the image.

[hsparikh]

Thanks for the feedback. There is a lot of work that still needs to be done to improve the UI for these tools, but our goal is to build a library of such visual tools for tens of relevant topics.

[cwlb]

I share your passion for revolutionizing math education, but I don't quite understand the attachment to "Common Core." Federal prescriptive nonsense is a huge obstacle for real innovation in education and outside of the need to make a sale I don't see why you'd limit yourselves.

[dxbydt]

personally, I feel uncomfortable reading stuff like "If the width is 2 units and the height is 2 units, the area is 4 square units since 2 times 2 is 4". 2 plus 2 is 4 as well, yeah ? As also, 2 ^ 2 = 4 The area is 4 regardless of what 2 times 2 is, or 2 plus 2 is, or 2 raised to 2. I get your intent, but the phrasing is questionable pedagogy at best.

[hsparikh]

Definitely agree with you, and the phrasing will change as we improve the design of these pages. Thanks for the feedback!

[tonylemesmer]

Does it work with touch? (I do not have a touch device)

[hsparikh]

The numbers should be draggable via touch.

[mcintyre1994]

They'd be quite small touch targets assuming you wanted to view the shape and calculation as you change them. Have you considered making the shapes resizable by dragging?