Overview

Grade 3 Math

Number

1. Describe and apply mental mathematics strategies for adding two 2-digit numerals

1.8 Addition with Tens and Ones

Addition with Tens and Ones (Place Value Addition)

Master adding two digit numbers by lining up tens and ones, using base ten blocks to see exactly what regrouping means.

What You'll Learn

Break each two digit number into its tens digit and ones digit before adding.

Add the ones column first, then the tens column, keeping digits lined up by place value.

Represent numbers with base ten blocks, using long rods for tens and small squares for ones.

Regroup by trading ten ones blocks for one tens rod whenever the ones total is 10 or more.

Write the regrouped ten as a small carried digit above the tens column before adding the tens.

Check an answer by re-splitting the sum back into tens and ones to confirm it matches the total.

What You'll Practice

Adding two-digit and three-digit numbers by tens

Solving addition problems with numbers up to 1000

Breaking numbers into tens and ones to simplify addition

Why This Matters

Adding with tens and ones builds your number sense and mental math skills, making everyday calculations faster and easier. This foundational skill prepares you for multi-digit operations, estimation, and problem-solving in all future math courses.

This Unit Includes

1 Video lesson

Practice exercises

Learning resources

Skills

Place Value

Addition

Tens and Ones

Mental Math

Regrouping

Number Sense

NS Curriculum Aligned