Lessons taught; Lessons learnt

I run a weekly maths club for a group of primary children in the area, and part of this involves creating or altering resources so that they can be picked up and understood by ten year olds. The first resource from the club that I'm contributing to this blog is my template and instructions for creating a trihexaflexagon.

While there are no shortage of flexagon sites, descriptions and videos around (and I particularly like the Murderous Maths one, as I've seen Kjartan perform, and he was very entertaining), there does seem to be a gap in the market for a simple blank template, together with a simple one-page instruction guide to putting them together.

Source: Inkscape SVG and PDF.

Source: Inkscape SVG and PDF.

I'm happy to work on producing similar instructions for the more complicated flexagons -- leave a comment if you'd be interested.

This term my school is running some maths competitions involving timed rounds. The questions are in Word, and I've been getting quite frustrated with the countdown timer built into Activstudio -- in particular, it makes resetting the count very fiddly. There are a lot of countdown/timer applications around, but the ones that do what I want seem to be either stupidly overcomplicated, not free, or to crash all the time.

To get around my frustrations I've cobbled together the following simple countdown timer, written in Javascript:

Source: countdowntimer.html.

Not particularly flashy, but it gets the job done!

You can start/stop/reset the countdown, and alter the starting count in 30s increments, just by pressing buttons, which makes it easy to use on an Interactive Whiteboard. In addition, if you click on the ^^ link (at the bottom right) the timer will open in a new window, with as few toolbars as your security settings allow.