Calculator Concerns

I have had many people, students and parents alike, ask me the point of learning how to do mental math when we have calculators.  I mean, it seems like students as young as elementary school students have personal devices these days, so they always have a calculator on them.  I can't argue that.

However, we cannot forget that calculators, like other pieces of technology, are tools to help us.  They do not replace our brains.  We still have to tell the calculator what we want to do, and it will give us an answer we may or may not reject (this is where number sense and mental math comes in!).

Calculators help us become more efficient, but here are some challenges around calculators that we must keep in mind:

1. A calculator is a piece of technology, and it must be explicitly taught.
Now that electronics are part of our everyday lives, it’s easy to forget that we don’t just learn how to do things by osmosis.  Back when I was in elementary school, we had computer classes, where we learned to type through software such as All The Right Type.  Students these days are expected to “just know how” and guess what?  They type with two index fingers at about ten words per minute.  Some skills just need to be taught and practised, and using a calculator is one of those skills.  Human error and syntax are two problems that can be minimized with practice.

2. We need to use the same calculator all the time.
Remember the previous point about how using a calculator is a skill that must be practised?  If a student uses one calculator at school and another calculator at home, how ready will that student be for a test at school, when they’ve studied for it at home?

The most basic of calculators have numbers, the four operations, and an equal sign.  These calculators do not have brackets, so imagine what happens when a middle school student tries to type in an order of operations question without the brackets.  The answer would be completely off, unless of course they were taught the appropriate way to use a calculator (i.e., only typing in the part of the equation that is being solved).  I suppose this particular problem – human error – wouldn’t exist if #1 was done well.

Another type of calculator is one where syntax matters.  Syntax is the order of the input of your numbers (e.g., square root button first and then number, or number first and then square root button?).  Calculators made today don’t really have this problem.  However, older calculators as well as those on devices (like the iPhone calculator) do care about syntax.  I have personally witnessed students using their device calculators (probably for the first time in their lives) on a test, and seeing the frustration on their faces because this supposed tool to help them actually messed them up.  Again, using a calculator is a skill that needs to be developed and refined.

For the purposes of proving that all calculators need to be practised, I will describe one more type of calculator that is usually free from human error and syntax problems, but we should still be cautious about.  These are the amazing handwriting-input calculator apps on devices.  An example of this is the MyScript Calculator (available on both iOS and Android).  These calculators recognize handwriting input and immediately solves it on screen, so it minimizes the chances of human error, since you can see exactly what is in the equation.  They also don’t care about syntax, because you can easily add or delete numbers and operations with the stroke of a finger.  What is a problem, however, is that handwriting input isn’t perfect at the moment.  

In my opinion, all calculators have potential for error (i.e., human error, syntax error, or other).  The only way we can minimize these errors is to make sure that we as teachers reinforce the fact that students need to always be using the same calculator in class, at home, and on assessments.