Estimation Teaching Resources

Are you teaching estimation in your maths classes? Make approximating easy with educational resources designed to help kids learn how to estimate and when to use these reasonable calculations.

With worksheets and activities aligned with the Australian maths curriculum (including the V9 curriculum!), this collection has everything math teachers need to build their lesson plans on estimating this school year. Help students understand the magnitude of numbers and prepare them for real-world estimating needs — from budgeting their shopping to estimating calculations when planning.

Do you need a refresher on estimation or some quick tips on teaching kids to estimate? Read on for a primer from our teacher team, including a look at the difference between estimating and rounding, what it means to approximate and more!

What Is Estimation in Maths? A Kid-Friendly Definition

We like to start with simple definitions of core concepts to provide our fellow teachers with a script starter for their lessons. So here's a way to explain the meaning of estimation to your maths class:

Estimation is making an educated guess or approximation of a quantity or value. This maths skill lets us make quick calculations so we can understand the amount or size of something without using exact numbers.

When we are estimating numbers, we aren't looking for an exact answer! We are looking for a number that is close to the exact answer — a 'good enough' answer.

How to Estimate in Maths — Different Estimation Strategies

Students tend to learn how to round numbers in year 2 or 3, which sets the stage for learning to estimate. After all, rounding numbers is one of the skills that students (and grown-ups!) use to estimate in maths.

Here are the more common methods we teach our students:

Estimating With Rounding

To estimate by rounding, you'll need to round your numbers to a given place or whole number. This will give you simple whole numbers that can then be added to estimate a sum, subtracted to estimate a difference and so on.

This process also works for estimating quotients and products.

Estimating With Benchmarks

If you are working with decimals or fractions, you may want to apply benchmark estimation. This estimating strategy makes use of common fractions such as 1/4 or 1/2 or common decimals such as .5 or .75, which are considered 'benchmarks' that students can round their given number to.

This simplifies the numbers at hand and makes it easier to then subtract or add.

For example, if a student has the fraction 7/8, they can compare it against the benchmarks 3/4 and 1, determining which benchmark it's greater than and which it is less than.

Estimating With Compatible Numbers

Compatible numbers are student favorites because it's easy to use maths mentals to add, multiply, divide and subtract them. For example, numbers that end in 5 or 0 are compatible numbers because they're fairly simple to work with when doing whole number operations. We often refer to compatible numbers as 'friendly numbers.'

Rounding a number to a compatible number simplifies the problem and makes estimation easier!

Estimation Examples in Real Life

We all have those students who like to ask why they have to learn a particular concept, and with estimation that question comes frequently. After all, estimating isn't providing the exact answer, so why is it valuable?

Your students may not even realize just how many useful applications this skill has, so let's look at a few ways to estimate in real life.

Estimating the cost of your items when shopping is an easy way to determine if you have enough money to cover the bill. You do not need to know the exact total price in this case. You only need to know that the amount of money you have exceeds the total cost of the items.
Estimating the amount of a certain item you need makes it easy to ensure you're creating or purchasing enough. For example, if you are planning a party, you may estimate how many cupcakes you will need to bake based on the number of people you expect to attend. You do not need to know exactly how many cupcakes, but it helps to have an approximate number.
Estimating the length of a table is an easy way to assess the number of people who can be seated at the table. It is also useful to estimate the size of items when you want to know if they will be able to fit through a particular doorway or window.