Journal of the Mathematics Council of the Alberta Teachers’ Association
Volume 48 Issue 2, June 2011
32 – 37
Subitizing: Part-Part-Whole of a Big Idea
Sylvia Malo
A continual cause for concern among many math teachers is how to help struggling students in our math classrooms. Some children who arrived in my Grade 4 or 5 math classes over the years struggled with number sense, and many came without the ability either to compose or decompose numbers or see part-part-whole relationships. The obvious breakdown in students’ conceptual understanding of part whole reasoning often occurred when students were asked to break up numbers into different parts and then recompose them or represent them in a different way. This was a common weakness for many students in my math classes and seems to still be an issue in many math classrooms today. After much reflection and searching, I have determined that one big idea in mathematics seems to provide more insight into why students struggle with number sense. This is my journey towards greater understanding of subitizing.
