This spring, Tom Francome very kindly invited me to share a “favorite lesson” with a group of teachers here in Birmingham, England. As befits a blog that’s all about foregrounding my failures, I chose a topic that I find really hard to teach effectively: the distributive property.
It’s so important (resonating across the whole of algebra); so simple (amounting to a basic fact about groupings); and yet so elusive (underlying loads of errors throughout schooling).
Here are the slides I used.
Here is the activity I shared (meant for 11- or 12-year-old students).
A few years back, I used this activity not to teach the distributive law to 12-year-olds, but the composition of functions to 16-year-olds. Here’s the original worksheet I designed (with some genuinely tricky questions!).