Browsing twitter recently I came across a tweet by Mr Hogg, retweeted by David Wees, that briefly outlined a quadratic graph matching activity that Mr Hogg had found really effective. A photo was included (see below).

In this activity students were given graphs, their equations in expanded and factorised form, and information about the intercepts. They had to cut them up, match correctly, then there was one graph with no information, which they had to fill in themselves.

The original activity, completed by a student.

As I was working on quadratic graphs with my Yr 11 class, I thought I would like to give it a try, but also wanted to add turning point form and the turning points as we had also covered these. The original file was not included, so I proceeded to recreate, with the extra turning point information, and one extra graph, so that there were 2 for students to complete.

Here is the Word document of the activity.

In the lesson I had students work in twos or threes, handed out an A3 sheet of paper, some scissors and a glue stick, giving them little instruction except to match the graphs with the correct equations and key features. They went straight to it. Many students started by matching all the intercepts, then moved to turning points. More confident students tackled one graph at a time. For me, it was an excellent opportunity for formative assessment, something I hadn’t really been thinking about when I decided to set the task. A few groups needed a prod towards connecting the factorised form to the x intercepts, or the turning point form to the turning point, but most quickly saw the connection and continued. The expanded form was the version that caused the most difficulty, but again, with a little thought, or a little help, most either used information about the y intercept, or expanded the factorised form. Once they had worked through the given information, very few had any trouble using the patterns that I had encouraged them to notice, to then complete all information for the final two graphs. By the end of the activity I had a much clearer view of exactly where students were in their understanding. The next lesson was a formal ‘writing equations from graphs’ lesson. It was good to see that most students were able to connect what they had done in this activity to the new work.