ICCAMS Maths Professional Development Session (7 March 2016)
Category : Uncategorized
We asked teachers at an ICCAMS Maths Professional Development session to give the following pre-lesson mini-assessment task to their students and to simply observe and listen to the responses:
The task looks at students’ awareness of how the relative value of two expressions can change. We got a wide range of responses to the task:
We also got a similar range of responses for 2n, n+2:
The task tends to reveal the following common misconceptions or misunderstandings by students:
Some students think that 2n is larger because it involves a multiplication. Greer (1994) refers to this misconception as Multiplication Makes Bigger, Division Makes Smaller (MMBDMS).
Some students think that n+3 can be simplified to 3n, so 3n and n+3 are the same (or equal). Some of these students justify this using “Brackets first” from BODMAS.
Some students think that the letter n represents a specific but as yet unknown number that the teacher “knows” and they need to either work out or guess.
What responses do you think your students would give? Why not give it a go…
