What Are Some Different Ways to Estimate With Decimals?

By now, your students are probably familiar with the traditional rules of rounding – 5 or more add one more, 4 or less, let it rest. When students enter year 6, they begin to use their understanding of rounding to round decimals and estimate with decimal operations. Let’s take a quick look at some different strategies your students can use when using their estimation skills with addition and subtraction problems.

Estimate by rounding – With this method, students will work to round to a given place, such as the nearest ten dollars, nearest whole number, etc. This will give students easy numbers to work with and make mental calculations fairly easy.

Estimate by benchmarks – Another method you may want to teach your students is the concept of using decimal benchmarks. Benchmarks are familiar numbers that are also easy to work with. When using decimals, these include 0.25, 0.5 and 0.75.

Regardless of the method your students are using, it is important to talk about how accurate an estimate is. It may be helpful to discuss with your students whether it is better to overestimate or underestimate when working with problems that involve money.

Elevate Your Students’ Estimation Skills!

Teach Starter has created a double-sided worksheet to help your students conquer the skill of estimating decimal sums and differences. This worksheet includes:

• Practise problems where students must round before adding or subtracting
• Practise problems where students must use decimal benchmarks before adding or subtracting
• Estimate the answer to 2 equations and compare
• Word problems

Download and Print Your Estimation Worksheet

Are you ready to use this worksheet with your year 6 students? Simply click the green download button and choose from the quick-print PDF document or the editable Google Slides file. If choosing the Google Slides option, please note that you will first be prompted to make a copy of the resource to your personal drive before accessing it.

This resource was created by Cassandra Friesen, a Teach Starter Collaborator.

More Resources for Your Estimation Lesson Plans!

Don’t stop there! If you are looking for more resources to add to your decimal sums and differences unit, check out the suggestions below!

teaching resource

Coffee Shop Calculations – Estimation With Decimals Task Cards

Download this set of 24 task cards to help your students practise estimating decimal sums and differences with benchmark numbers.

teaching resource

Estimating Decimal Sums and Differences — Year 6 Worksheet

Refine year 6 students' rounding skills with an estimating decimal sums and differences worksheet.

teaching resource

Estimating Decimal Sum and Differences — Year 6 Maths Mazes

Year 6 students can practise estimating solutions to decimal addition and subtraction equations with this set of maths mazes.