Dr Nic’s blog

11 May 2020

Not all uses of equals signs are equal

The problem with equals signs The sign “=” was invented in 1557 by Robert Recorde a Welsh mathematician. He was tired of having to write out the phrase “is equal to” too often. Now we cannot imagine maths without an = sign. Using an equals sign correctly can be a challenge. Whenever an equals sign is used, it signifies that the expressions on either side are equal. A sequence of expressions separated by equals signs should all be equal to each other. For example: 4 + 5 = 3 × 3 = 21 – 12 However, the equals sign often […]
18 March 2020

Resources in maths and stats for a pandemic

We live in interesting times. It warms my heart to see my discipline of mathematical modelling used to predict and manage the outbreak behaviour. How much easier it will be to explain Operations Research after this! In New Zealand we have yet to feel the full force of the Covid-19 pandemic, but anxiety hangs in the air. Around the world schools and colleges are closing their doors to slow the spread of the virus and students and teachers are forced to enter the world of distance learning. Nine years ago the Christchurch earthquakes meant that the University where I worked […]
24 January 2020

Fraction Addition and Subtraction with the Denominator-ator

Adding and subtracting fractions is tricky. Many of the adults I teach are confused when it comes to fractions. It can be difficult to remember that addition and subtraction of fractions require common denominators, which stay the same when you add and subtract, while multiplication operates on both the numerator and the denominator. I have written about this: The big deal about fractions Fraction addition confuses. A fraction operation such as 2/3 + 3/4 requires five operations to get the two fractions to a common denominator and then add the numerators. It can be difficult to explain why this is […]
26 November 2019

Creating and critiquing good mathematical tasks with variation theory

Variation Theory applied to teaching mathematics and statistics Highlights Careful selection of exercises can turn purposeful practice in maths into a task that also develops conceptual understanding. Poor, off-the-cuff or random selection of exercises can create barriers, feed misconceptions and at best miss out on opportunities for better learning. Using a framework of variation theory can help teachers examine and improve their practices and tasks, preferably collaboratively Spurious rules If students can learn a spurious rule for answering questions rather than the desired concept, they will grab it with both hands. In my class a student worked out that if […]
12 September 2019

Talking Maths in Public

Three types of people There are three types of people in the world: those who can count and those who cannot. Just kidding. But the ways people respond to mathematics can be put roughly into three groups – the maths-likers, the perplexed and the traumatised. See “Writing about Maths for the Perplexed and Traumatized” by Steven Strogatz. Maths-likers Strogatz uses the term “naturals” for this group. The maths-likers are people who liked maths at school and find it interesting. Some maths-likers go on to become maths teachers or accountants or statisticians or work in some other area that uses mathematics. […]
12 August 2019

How to help your child with her multiplication facts

Multiplication facts matter Fluency with multiplication facts makes learning later skills easier. When simplifying fractions, it is helpful to know multiples of numbers. When learning division algorithms, fluency in the basic facts means that the brain is free to learn the new procedure. In algebra, it is extremely helpful to be able to recognise common factors of two numbers, such as 36 and 24. Being fluent with multiplication facts is invaluable for estimating in many areas of life. A recent survey of high school teachers reported that they value knowledge of tables highly. Parents helping The advantage a parent has […]
19 June 2019

Fluency in maths

Fluency in language I can recite Latin verbs: the present tense of love is amo, amas, amat, amamus, amatis, amant. I recited them as I swam up and down the pool forty years ago: Amabo, amabis, amabit (breathe) amabimus, amabitis, amabunt (breathe). But if I were suddenly faced with an ancient Roman and had to express my affection, it would take a bit of thinking. I lack fluency in speaking Latin. When we are fluent in a language, we can respond and converse without having to think too hard. The language comes naturally, and we do not use up space […]
5 June 2019

Achievable challenge in teaching maths

I like a good challenge I always choose the most difficult Sudoku puzzles. I like it best if I get really stumped and have to leave the puzzle and come back later. If I do manage to crack it, I feel a sense of achievement, and completion. From time to time I have tried “The most difficult sudoku” but have never managed to place more than one number. There isn’t a lot of fun in that. Fun exists in what is sometimes called “The Goldilocks zone” – not too easy, not too difficult, but just right. I have also seen […]
8 May 2019

Like, Share, Comment, Subscribe, Join – YouTube!

Like, Share, Comment, Subscribe, Join – YouTube YouTube has an enormous impact on the lives of millions. Creators, young and old, are supplementing their income, or making a fortune through posting an unthinkable range of content. Some is uplifting, educational, funny, entertaining, diverting and nostalgic. Some is less positive. My son who is blind gets a great pleasure from ‘watching’ YouTube clips of old game shows, children’s programmes, and even Sesame Street. When I want to know anything – how to crochet, how to fix a tap, how to use Adobe Illustrator and so much more, I look for a […]
1 May 2019

The big deal about fractions

Fractions are a big deal When you ask people what topics in maths they like and dislike, fractions tend to appear in the dislike column – often vehemently. Recent polling found that maths teachers think fractions are important for students entering High School. I teach in a career course in maths for people who have missed out on maths on the way through school, and a large component of that is fractions. I love fractions. I prefer them to decimals because they are more exact. One seventh is so much neater than its decimal equivalent. I like adding fractions and […]