Tuesday, April 12, 2011

Conventional wisdom alert -- Who needs a graphing calculator?

Both Mike Croucher and John D. Cook have posts up questioning the use of graphing calculators in mathematics instruction. As Croucher puts it:
If you are into retro-computing then those specs might appeal to you but they leave me cold. They are slow with limited memory and the ‘high-resolution’ display is no such thing. For $100 dollars more than the NSpire CX CAS I could buy a netbook and fill it with cutting edge mathematical software such as Octave, Scilab, SAGE and so on. I could also use it for web browsing,email and a thousand other things.

I (and many students) also have mobile phones with hardware that leave these calculators in the dust. Combined with software such as Spacetime or online services such as Wolfram Alpha, a mobile phone is infinitely more capable than these top of the line graphical calculators.

They also only ever seem to be used in schools and colleges. I spend a lot of time working with engineers, scientists and mathematicians and I hardly ever see a calculator such as the Casio Prizm or TI NSpire on their desks. They tend to have simple calculators for everyday use and will turn to a computer for anything more complicated such as plotting a graph or solving equations.

One argument I hear for using these calculators is ‘They are limited enough to use in exams.‘ Sounds sensible but then I get to thinking ‘Why are we teaching a generation of students to use crippled technology?‘ Why not go the whole hog and ban ALL technology in exams? Alternatively, supply locked down computers for exams that limit the software used by students. Surely we need experts in useful technology, not crippled technology?
The only thing I'd add is the need for spreadsheet literacy. In the past twenty years, I have never seen anyone using a graphing calculator outside of a classroom and I have never come across a job, ranging from the executive to the janitorial, where Excel skills don't come in handy.

When I was teaching I taught all my kids to graph functions on Excel. If I were still teaching high school, I would strongly consider making something like Scilab or Python part of the curriculum (particularly for calculus), I might even consider requiring all students to have at least one programming based math class but I would still insist that all students knew their way around the graphics package of a spreadsheet.

In general though I think we're in general agreement that student should be taught technology that they are actually going to use.


  1. I agree with this totally, but I'd add that Microsoft products are expensive and schools could stretch their budgets a lot further by using open source software. As it is, the kids in Africa who are being taught on cheap netbooks almost have an advantage over American kids, who spend their computer lab time (if they have a computer lab) learning the ins and outs of GUIs that will change by time they graduate, anyway.

  2. Sloppy writing on my part. I meant Excel or an open-source alternative (I'm an Open Office guy myself).