1 February 2015

5 Maths Gems #23

It seems like ages since my last gems post. School has been busier than I anticipated. This week I had reports to write and a Parents' Evening to attend - both tasks were particularly challenging because I've only been teaching these classes for a few weeks. I've also been marking at home every evening so it's hard to find time for Twitter and blogging. I have three other posts in draft - one about teaching quadratics, one about spontaneity and one featuring another batch of highlights from Chris Smith's newsletter back catalogue. So watch this space, they're all coming soon! In the meantime, here's five ideas you might find useful.

1. Perspective
I've been teaching 3D visualisation to my Year 7s this week (isometric drawing, plans, elevations and nets). I've decided that this is one of my top three 'worst topics to teach' alongside constructions and transformations. But it did give me an opportunity to use the picture below, which I got from Twitter a few months ago (original source unknown - please tell me if you know!). I put it on the board when my students arrived for their lesson on plans and elevations.
2. Etymathology
My new favourite Twitter account is @etymathology. They share information about the origins of mathematical words - the sort of fascinating information that we should be sharing with our students whenever we introduce new vocabulary. I wrote about the importance of this back in Gems 10.

This week @BedtimeMath shared this fact about seconds, which I'd never heard before:
It's funny how we can use a word like 'seconds' our whole lives and never give any thought to where it came from. Etymathology followed this tweet with the origins of the word minute:
And there you go - another example of Twitter's contribution to education. I acquired new knowledge to pass directly to my students. I look forward to learning more!

3. Match My Parabola
I've written about Desmos many times, most recently in my post Polygraph Rocks. I'm always keen to hear new ideas for teaching with Desmos so I loved Michael Fenton's (@mjfenton) post 'Match My Parabola'.
The post describes a lesson suitable for Higher GCSE or Core AS students studying quadratics. The idea is that students are given a set of coordinates and have to find a quadratic function that passes through them. Michael very helpfully provides 10 activities - all your students have to do is click on the links and complete the tasks (here's an example for you to have a go at - enter your function in cell 9 on the left to see if you're right).

Michael has previously written about 'Match My Line' - a similar lesson but for linear graphs, suitable for Key Stage 3 or 4. I've found that students of any age love playing with Desmos so I'm looking forward to using this one too. Really clever ideas from Michael.
4. Valentines Relay
It's only two weeks until half-term! Friday 13th February would be a good day to do Chris Smith's (@aap03102) lovely Valentines Maths Relay Race.
5. War on Error
Do your students keep making the same mistake? Highlight common misconceptions in a display using Mr Taylor's (@taylorda01) War on Error resources - see his post for full details. This week one of my students wrote (x + 5)2 = x2 + 25 so that would be my first entry to the display!
That's it for my gems this week, but bear with me - I have a few more things I want to tell you about...

Multiple Choice Tests
I wrote about multiple choice tests and Quick Key in Gems 11. This week I tried it out for the first time. Like my first attempt at using Plickers, it wasn't very successful! But I do intend to try both apps again - I think they require a bit of practice.

Quick Key is an app that scans multiple choice tests and gives you instant feedback on results. I found it very easy to set up - I wrote a short quiz on quadratics and simply entered the correct answers to Quick Key as I wrote it. In the lesson, I gave my students 20 minutes to make themselves a one page summary of everything we'd covered on quadratics, and then I gave them a 20 minute quiz in which they were allowed to refer to their revision sheet.

I was excited about marking the tests using Quick Key but I found it very hard to find a shadow-free, glare-free place to scan. In the end it took just as long as if I'd marked them by hand. The test results varied from 20% to 100%, with most students getting 80% or 90% (the most common error was choosing A instead of C in the question below). So it was a successful exercise in assessing the understanding of each student and confirming that the majority of students were ready to move onto the next topic, and now I just need to figure out how to address the gaps with those who got a low score.
So in summary, the lesson in which students made a revision summary then took a short multiple choice test was successful, but I'll need to get the hang of Quick Key.

World's Hardest Geometry Problem
I've just finished teaching angles to Year 7 and was really impressed when one of my students told me that she'd found an angles problem online and had spent two hours working on it over the weekend, but even with the help of all her family she couldn't solve it. It turned out to be the 'World's Hardest Easy Geometry Problem' which I've featured before... I promised her I'd have a go at it this weekend - I suspect I may end up asking Twitter for help!

Don Watch
Have you been keeping an eye on all the brilliant new resources on Don Steward's blog? His recent post about sequences, 'Jumping along a line', suggested using the 0th term to work out the nth term of a sequence. This isn't how I usually teach sequences but I'll try it next time.

I also spotted the 0th term on a Pret homework that Grant Barker (@AccessMaths) sent me this week. We've now got more than 100 homeworks on prethomework.weebly.com so if you're ever looking for new homework ideas then do check it out.
Mr Maths
Finally, I'll leave you with one of the fantastic images made by @solvemymaths this week - check out his blog for the full 'Math Mr Men Series'.


  1. Jo, thanks for the link and the kind writeup! I'm amazed by the vast collection of resources you post here, and honored to be included in a couple of posts. Up next... Match My Graph with power/exponential/logarithmic functions.

    Cheers! :)

    1. Thanks Michael. I love all the lessons on your blog and I'm looking forward to the next Match My Graph!

  2. Katherine Barker2 February 2015 at 09:19

    I'm taking the geometry problems to the next Mathsjam (anyone else in London - I thought of it first!)

  3. Jo - that square-circle-cylinder picture: did you see the sculpture, "squaring the circle"?

    1. I'd not seen that, thank you. Lovely sculpture. I'd also not seen your website before - looks great, lots to explore. Thanks for the link!

    2. Oh, and I'd struggled with that hardest geometry problem for a while - before giving up!

    3. I'm afraid to say I've given up too!