02 November 2012

Desmos Updates Web-Based Calculator: Ready to Ditch Your Old TI?

Desmos, Inc, creators of a great online graphing calculator just updated the interface and functionality of their web-app, but is it enough render other apps or traditional calculators obsolete?

There are advantages to your students utilizing web-based, iOS/Android, or physical TI (or Casio) graphing calculators, so if you've got the resources, use them all!

Software, hardware, and mobile apps all have their place in 2012 maths education.

Appropriate Uses:

Desmos (and other) online graphing calculators

You live on the web, you work on the web, you publish on the web. Why are we still forcing our students to make and analyze function and statistical graphs on a separate piece of hardware and (at best) uploading them to PCs via USB? 

Especially with Algebra 1 or Geometry students, I feel like there is a ton of instructional time spent just teaching navigation through menus and screen on traditional calculators. The beauty of the Desmos interface is that almost every utility your Algebra students might use is all together. Equation editor, tracing, and graph view doesn't require any extra keystrokes. Instructing use of the Desmos Calculator is usually limited to answering "How do I add a new equation," and "What do you press for the exponent?" and the students quickly figure out the rest as they play.

Editing equations on this web-based graphing calculator also seems like training wheels for other math software like MathmaticaWolfram Alpha, or Geogebra

The real power of Desmos, is how they've built sharing right into the app. 
With a button that looks VERY similar to the Google Docs share button, you've given a hypertext link, mail link, embed code, and image download. Very flexible!
You could:
  • use the sharing feature to upload your own graphs onto your class website
  • post to your class social media pages
  • embed into assignments/quizzes/exams

Your students could:
  • Share on wikis
  • Share on discussion/message boards
  • email you
  • email each other
  • Post on their social media accounts

Mobile Apps or Software Based Calculators

I haven't really found one that has anymore functionality than the free Desmos calculator, but these are handy to have on my iPads or the math computer lab for when the network is down. The practice of typing mathematical equations is also important for success on our Missouri Algebra I EOC. It'd be a shame for our students to score poorly because of the technology instead of a lack of knowledge. 

Students are also always willing to download a free version to their mobile devices. Searching in your app store will get you one of several free or cheap options. The favorite for my class iPads is (you'll never believe it) "Free Graphing Calculator". My preferred software for high schools is the open source GeoGebra platform. It is very similar to Geometer Sketchpad, which is written into many textbook's curriculum, and (like Sketchpad) also has an archive of lessons and resources.

Traditional graphing calculators (TI-83/84/NSpire or Casio Fx or Prism)

Students taking standardized tests still have no other options for their graphing/statistical needs than the golden standard dedicated graphing calculator. It seems obsolete and an inefficient use of resources to me, but its also irresponsible to neglect training on operation (and encouraging/requiring students to use them). If your math students are spending all of their time sketching simple graphs on their ACT, SAT, or AP (or your Praxis II) scratch paper, they will run out of time to do the analysis that is truly required on the assessments. Until the testing companies find a way to block students' use of other apps during testing, laptops, tablets, and smartphones will continue to be banned from the testing environment.

Besides testing, endurance also lies on the side of TI. Although it seems crazy to me that they still sell TI-83s for 80-90 dollars, that's actually great for your attempts to integrate the technology into your classroom. The keystrokes for most basic functions on TI or Casio hardware haven't changed since at least 2000, so you can reasonably use class sets your school has previously purchased within the past 12 years. Can you imagine getting a reasonably similar experience for your students between a 2000 iBook and a 2009 MacBook (The year before TI-Nspire was introduced). We have almost 40 old TIs we still use in a bind.

What's your preference for your students' graphing needs? Given limited instructional time, which approach would you prioritize?


  1. Thanks Chuck! We appreciate the kind words.
    Stay tuned for even more amazing upgrades in the near future - especially for mobile devices :)
    Happy graphing,
    Team Desmos

  2. This will always be a Desmos fanboy blog. :) (among other things)

  3. First off, I love Desmos. It is extraordinary. I agree 99%. Except the 1% of me that says they aren't allowed any other tool except a grapher or scientific, which really stinks. Unless there is some way around this I have stated in my math classes that Desmos (clearly awesome!) should only be used a supplemental tool. Any comment?

  4. I agree completely. I don't like it, but I have a responsibility to make sure my kids can still work their way around a traditional calc, no matter how less useful they are.

    What are your thoughts on the new TI 84 color?


Thanks for sharing!