Using a calculator effectively in core maths exams
21 October 2024
Gerard Dummett, Maths Technology Consultant
Students often use calculators for simple arithmetic operations, but are your students tackling complex exam problems efficiently and accurately? Do they use all the functionality of their calculator? How confident are you in all the functionality? In this post I’ll explore how you can integrate scientific calculators into your teaching, giving your students a much better chance to use them effectively in exams.
Quick summary
My top three tips for accurate and effective use of a scientific calculator in exams are:
- use efficient multi-step calculation
- use calculator memory
- know how to use number formats.
Get the basics right
Make sure that the calculator your students use displays maths naturally (fractions, square roots) and follows BIDMAS. Most scientific calculators do this, but check particularly on cheaper scientific models.
Know how to reset the calculator. This can be important if a special setting such as a fixed number format has been used.
Efficient calculation
Encourage students to enter the entire calculation where possible rather than breaking it into steps. Examples could be calculating the area of a circle (entering pi, radius and the square in one go) or evaluating a formula (entering all terms in a single calculation).
Using fractions for division is especially useful to avoid BIDMAS errors. They are also useful for percentage calculations, with the additional advantage that this represents proportion of a whole.
If several calculation steps are required, use memory. This could be specific memory stores or the ANS facility. Better calculators have multiple stores and the option to display as well as recall the value.
Number formats
Most scientific calculators offer number formats for fixed decimal places, and standard form with significant figures, in addition to standard fraction/decimal output. Make sure your students know how to use these formats – they can be useful for questions where there is an accuracy mark for a specified format.
However, be careful – don’t forget to reset the calculator for the next question, or accuracy may be compromised.
Ratio
Ratio is a really good way of teaching proportion, which is arguably one of the most important maths concepts. Ratio can help with topics such as:
- exchange rates
- percentage change
- reverse percentage
- linear graphs
- scaling
- fractions of a whole
- direct proportion.
Layout of the calculation is important – and not just for method marks. It’s worth emphasising how to extract information from the question. Then practice entering the information in the calculator using the methods we’ve discussed. That should increase accuracy.
Casio calculators include a ratio app (unfortunately this is not currently available on other calculators). Even if you don’t use this app or calculator, consider how fractions can help – and how to use them on a calculator.
A word about teaching
Calculator use in the exam will be more effective and accurate if you use calculators in class. Students need an opportunity for guided practice. Try to incorporate calculator-based activities as you feel appropriate and do so from the start. An emulator, if it is available, is invaluable for demonstrating calculator skills.
Beyond this, though, are teaching strategies for specific topics that harness the calculator to deepen understanding. Quite apart from taking the computation load, they allow students to explore and so consolidate their understanding. Real-world examples in core maths provide a good opportunity for this exploration.
Our video on using technology for teaching, available on Teach Cambridge, illustrates the techniques discussed in this blog and suggests strategies for topics such as multi-step calculations, number formats, percentages and exchange rates. It also introduces spreadsheets as another learning technology. Providing your students with the opportunity to work with spreadsheets in the classroom will improve their understanding of standard form number formats and use of formulae in spreadsheets. For Core Maths B students, it also gives them an opportunity to become more familiar with the large data set which they are assessed on in the statistical problem solving component.
Addressing common challenges
Students may encounter difficulties when using calculators. If you incorporate calculators into lessons, you will be able to support and guide them. Specific things to watch out for are:
- entering incorrect digits
- not following BIDMAS
- use fractions or brackets
- using rounded intermediate values
- use memory
- reset number format
- non-credible results
Where next?
We’ve looked at some strategies for more effective exam use of calculators. I’ve also suggested looking at incorporating calculators into your teaching to deepen understanding.
I’d recommend looking at the video on Teach Cambridge for guidance and ideas on how to use spreadsheets to enhance learning. I’d also recommend exploring the calculator your students use yourself. Take a look at the manufacturer’s website to see if they have resources to support calculator skills, and maybe even teaching ideas.
Stay connected
Share your thoughts in the comments below. If you have any questions, you can email us at maths@ocr.org.uk, call us on 01223 553998 or message us on X (formerly Twitter) @OCR_Maths. You can also sign up for subject updates and receive information about resources and support.
If you are considering teaching any of our qualifications, use our online form to let us know, so that we can help you with more information.
About the author
Gerard has an abiding interest in using technology in maths and has extensive experience of many types and brands of calculator. He was a head of department for many years and latterly Casio’s education manager, so got to know calculators (not just Casios) even better. He has been independent for some time now, supporting and training in a range of maths technology, including professional development for OCR. He believes that the most important thing is that maths should be enjoyable and the technology accessible. All this leads to exam success!
Related blogs