TickTockMaths

Tag: smsc

  • Misleading Graphs

    image

    I was shown this corker of a graph recently. The scales there are wonderfully deceptive.

    I love a good misleading graph. They’re really good for generating discussion, especially when you delve into the difference between a graph merely being wrongly created and a graph that’s been deliberately manipulated to be misleading, as this one has.

    I’ve put together a selection of my favourite misleading graphs in this PDF.Obviously you don’t have to use them as worksheet, you can cut them out and use them however you want, or simply display them on the board to talk about.

    If you use this resource, let me know how you get on in the comments. I’d love for this resource to generate discussion about how it generated discussion.

    Edit : DataBlog Ammp3d (a blog that I will talk about here at some point) posted a funny correction to the Conservative graph on Twitter, which is well worth discussing.

    ammped

  • Designing a diet

    Tutor Time Videos is a great little website full of videos to show to your class. In tutor time. One video in particular, however, made me think of an interesting idea for a lesson. It’s a video showing what amount of different foods is equal to 200 calories. You can watch it below.

    http://www.youtube.com/watch?v=KMGUmcveQeg

    A good way into the lesson might be to show different meals, and ask students to take a guess how many calories are in each. Most cooking websites list calories next to recipes if you want to find some examples.

    You could then show them the video. The video also links to a website here which gives a nice list and visual representation of 200 calories of different foods. You could print this out and give the list to students. You might then want to ask them to refine their initial guess based on new information.

    At this point, I’d reveal the answers.

    You could then give students 3 scenarios. For example:

    Ben

    Ben is happy with his weight. In order to maintain it at his current level, he needs to eat 2500 calories a day.

    Kate

    Kate is underweight. To make sure she is more healthy, Kate needs to make sure she’s eating 2200 calories a day.

    Simon

    Simon wants to lose weight. To do this he needs to eat 1700 calories a day.

    Then you could ask students to design a diet for each of them, trying to stick as close to the intended calorie target as possible.

    To make the task more rich, you could even ask students to look at home and find their own data for the calorie content of foods in their cupboard.

    The mathematical skills used here would not be hugely advanced, but this kind of task is all about the application of that maths and trying to stay away from a simple ‘234 + 456’ contextless question.

    If you try this, please report back with how it went. I’m going to give it a go with my nurture group and put a follow up post on here soon.

    Hat-tips to David Gale for inspiration. Follow him on twitter @reflectivemaths and to Adam from my maths department who suggested the initial guessing idea which I think adds a lot to the task.