Graphing Calculator Workshops

I’ve had a really nice time doing a round of workshops for teachers and for PGCE and GTP students on handheld technology. I’ve always thought that ICT provides opportunities for teachers to invent interesting activities that give students deep insights into how maths works. It is interesting that today, pupil’s in primary schools are no longer to be allowed to be examined in their ability to solve problems with numbers harder than those they could handle by written or mental methods. Calculators are banned. Bizarely, the minister responsible justified this move in terms of the need to be able to handle numbers because maths “influences all spheres of our daily lives”. This maths is routinely done by engineers and scientists who would never stoop to using a calculator or indeed a computer to support their number work. The failure to get the sums right in the recent Virgin trains debacle was presumably caused by over use of calculators, except that the culprits will have been educated in an era when they did have get enough number work. An era that clearly never was.

I start with the neat teacherly trick of playing ‘guess the function‘ here the participants see a calculators giving values of f(x) for their values of x, letting them choose to get a feeling for the variation. I only show them a graph, when they have already formed a reasonable view, then watching as they focus on the details. The first thing is to realise that experienced teachers and well qualified trainees struggle to see a quadratic just form a small table of values. No doubt because the drill and practice pedagogy the present government is so enamored with means many will have only ever encountered a quadratic already knowing that was what the five points they were given to plot would show. But it is good to get a feeling for things and they see this. So, playing the game on the handheld with their partners strengthens the insights and makes them more flexible.

It turns out that lots of schools are buying sets of iPads, demonstration that there is plenty of money around. But the maths software available for iPads isn’t a patch on any graphing calculator and the storage, security and battery issues for anything you have to recharge means they will be no more reliable than laptops. In one group of 25 trainee teachers after about 4 weeks in schools only one had seen any handheld machines possible to use in ordinary classrooms. That was a school where every student carried a laptop with them at all times. It only came out later that in all this time they had not been used even one single time in maths lessons. A set of 15 HP39gIIs stored in a bag in the maths office with a few spare batteries and you just pick them up on your way in to class. I make the case that it is the teacher who prevents the use of technology. That is a bit harsh. Mostly it’s the technology. So use something which is no more expensive than a couple of textbooks and is almost certain to work.

Then we get back to seeing the resources we have as sites to conjour up really clever ways in to mathematical ideas. That’s what makes our job fun. Look at bag of dice, counters, centicubes and we should always be saying, OK what could I do with those that encapsulates a mathematical idea. A graphing calculator is just the same, it’s something we can use to give students deeper insights. It is in fact a calculator, and the scientists and engineers of the future should certainly learn to use it to support their number work, their algebra, whatever, so they can focus their brain power on being brilliant with the science and the engineering. But also it’s a pedagogic device. A clever piece of kit for clever teachers to do what is most creative about our jobs. Something that supports kids doing clever thinking.

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