I have attended the two Maths Jam conferences – 2010 near Stone and 2011 near Crewe. At each I gave two talks, one of each I have written up over at Second-Rate Minds, the mathematics writing blog Samuel Hansen and I share over at ACMEScience.com.

Most recently I wrote up my 2011 talk Why the hot light bulb annoys me. In this I describe a puzzle which annoys me and explore why this is the case through a couple of other puzzles:

The light bulb puzzle presents you with three switches, one of which controls a light bulb inside a closed room. You are permitted to flip switches as much as you like, then you must open the door and say which switch controls the light bulb.
You don’t seem to have enough information. You can flip one switch and open the door. If the light is on then you have found your switch. However, if the light is off you can’t tell which of the other two switches controls the bulb.

My first post over at Second-Rate Minds was a write-up of my 2010 Maths Jam conference talk Moving on a strange diagonal. In this, I describe a puzzle I have given to students and why I like what it reveals about their thinking.

Given a 4×4 grid of sixteen dots, draw six straight lines that form a continuous path passing through all of the dots. Here, continuous means you must be able to draw over your six lines in one go without taking your pen off the paper.
This task is easy to complete with seven lines and impossible with five. Six is where the interesting puzzle lies.

The way Second-Rate Minds works each of these posts was written by me with Samuel Hansen providing editorial direction.