Believe it or not, I do actually have some good news to share.

Our decimal number system is a place value system. It was designed to be used in columns, and finally, the Ministry of Education agrees. The nzmaths.co.nz website has published new resources for teachers to support early learners with addition and subtraction of two-digit numbers, recording the calculations vertically! Column addition is officially making a comeback!!

Although these resources are intended to support students “not on track to meet the expected level”, absolutely no student should miss out on this foundational learning. If you are a parent whose child has been told by their school that they are not allowed to line up the columns, you can now politely refer to these resources and reassure your child’s school that it is officially okay. If you have a learner who is struggling with the “renaming/regrouping” method of column subtraction, you can show them the “borrow-and-pay-back” method, which is much easier to apply.

How far the nzmaths.co.nz website has come, proffering answers such as “Teachers should debate whether they will introduce the written form at all” and “Early teaching of the written form often locks students into low-level thinking from which they never emerge” until I called them out in 2013.

Please share this news widely, especially among teacher groups. Teachers already celebrating the column-based methods are seeing the benefits: their students’ understanding and problem solving are noticeably improved. In other words, they have been unlocked from low-level thinking and are now emerging! This is not a surprise if you understand the cognitive science of learning.

After two decades, the return of early column addition doesn’t feel so much like a victory, just a huge relief. Now, we can really start to fix New Zealand’s big maths problem.

Dr Audrey M. Tan
16 September 2022