Rounding: Part 1 Why Teach Rounding?

Rounding is a key maths skill that cannot be underestimated. (Pardon the pun!). Sometimes, as busy teachers (or parents), we see rounding as just another unit to be completed as we rush through our busy curricula. Quick - tick it off the plans. But to do this, is to miss the fundamental importance of rounding in building maths foundations, skills and number sense.

Three key reasons

There are three key reasons to teach rounding:

1. Number sense and structure: Rounding helps children to map where numbers fit and helps them to develop an understanding structure of number.

2. Estimation and computation: Rounding is a very useful strategy to help children to calculate more easily and estimate.

3. Other curricular skills: rounding helps children in other areas of maths, for example telling time.

1. Number sense and structure: We can, as adults, underestimate the level of explicit teaching and practice that most children need to properly understand our number structure and system. If we teach rounding properly, children get a chance to map numbers and to figure out that there is a structure and a system and not just a random set of numbers that don't follow a pattern. There are, of course, children that understand and grasp this effortlessly, but many children benefit from explicit teaching and repeated practice. This is particularly important for children with dyscalculia or other learning difficulty. As with dyslexia and reading, there is no substitute for structured, systematic learning.

2. Estimation and computation: "Roundy numbers" are much easier to add mentally. For example, 48 and 31, becomes 50 and 30, which is much easier to add. So, I have a rough idea that 48 and 31 is around 80. Being able to estimate and add / or subtract numbers like this is very important. Rounding is a very useful tool for estimating.

3. Other curricular skills: Rounding is an important skill across all strands of the maths curriculum and across all areas of life. Being able to round is important for telling time (55 minutes is about an hour), data (493 people is nearly 500) and measures (about 1,879 metres is about 2,000 metres). It is particularly important for teaching everyday life skills such as money.

   Sometimes, we shy away from teaching rounding to children with learning difficulties but it can be a particularly useful skill to teach, especially in the context of real-life maths.

I’ll go through the steps for teaching rounding effectively in my next blog posts, including some of the common difficulties children encounter and how to support them.

If you would like ready-to-use materials in the meantime, you can also find my Rounding Pack, with teaching slides, practice materials and practical scaffolds, in my TPT store here.