Friday, 25 March 2016

Make a Fraction Talk Square

Nat Banting got me working out how to screencast with the Smartboard (and spotlit it too). The sound's still not good, but I'm hoping I'll work that out.

One of my first recordings was this, during a fraction talk.

I was glad I followed up Beatriz's question and we made them with Geogebra:
It was a great way into Geogebra apart from anything else - simply using Midpoint and Segment tools (Click on the tools second and third from the left.)

We only used the two tools and yet the students had a lot of freedom - they produced some interesting squares. We talked about two of them, that involved halving in particular.
The other two involve an interesting feature of triangles.

I'm wondering if someone will say that the triangles on the left of Maria's square are the same area? Or the small ones on the top right of Beatriz's? And where do we go from there?

Code to embed the Geogebra app:

<iframe height="556px" scrolling="no" src="" style="border: 0px;" width="1007px"> </iframe>


  1. So much good opportunity for reasoning here. How do you think students will investigate Maria's possible eighths? And I love Beatriz's floating sixteenth square.

  2. Yes, it seemed too good too let go - we gave most of the lesson to it today. Was pleased with the thinking - and especially with Maryam's claim.

    Even though I've got an idea to put before them, I'm not entirely sure of the best way to ask the class to investigate her claim...