In preparation for Global Math Week, my colleague, Dan Allen, and I held a number of sessions for interested teachers to introduce them to the idea of exploding dots and how they could incorporate this into one of their lessons that week:
For Global Math Week itself, I went into Grade 2, 3, 4, and 7 classes. The students really liked the idea that they were part of a worldwide event and that they were solving the same problems as students in Australia, China, India, Germany, Tanzania or wherever they had friends and relatives.
I started with simple 2 to 1 and 3 to 1 machines. Here, a grade 4 student is writing 7 using a 2 to 1 machine. Listen to all the kabooms happening in this clip:
For the Grade 4 and 7 students, I then tried a 3 to 2 machine.
Kabooms galore! It was neat to see the students taking care to make sure that they did the explosions correctly and checking with each other to see if they got the same result. Where they were discrepancies, they sought to convince each other of the correct answer.
Finally for the Grade 7s, I tried an operation with them using a 3 to 1 machine:
This they did with no further instructions from me:
I tweeted my excitement to James Tanton who then sent me another challenge. When I got stuck into this, something so surprising and wonderful happened, that I experienced what can only be described as 'Math Bumps':
Joyous maths indeed.
My sincere thanks go to James Tanton and all at the Global Math Project for helping to spread joyous math everywhere.