Doubles Background Information for Teachers, Parents and Caregivers
This page provides information to support educators and families in teaching K-3 students about doubles. It is designed to complement the Doubles topic page on BrainPOP Jr.
Many young learners use their fingers or counters when they first learn to add. Help your students learn strategies that help them add and subtract faster. Memorizing doubles facts will help them manipulate numbers and empower them to use multiple strategies to approach math problems.
Review with your children that a doubles fact is a number sentence that repeats the same addend, such as 3 + 3 = 6 or 8 + 8 = 16. Using manipulatives or other classroom materials, give students opportunities to practice combining groups with the same number. Record their number sentences on a chart for the class to use as a reference tool. Encourage your students to memorize doubles facts by making flash cards or making up songs, stories, and poems. Help them understand that they can use doubles facts to solve other number sentences too.
Ask your children to find the sum of 5 + 6. They can use counters or their fingers, but they can also use doubles facts. If they know 5 + 5 = 10, they know that the sum of 5 + 6 will be one more. Thus, 5 + 6 = 11. Practice solving other doubles-plus-one facts together, such as 3 + 4, 7 + 8, and 9 + 8. Make sure children write down or say the doubles facts that can help them solve the equations. They can also use doubles-minus-one facts to help them solve equations. Write down 9 + 10 and have your children find the sum. If they know that 10 + 10 = 20, they know that the sum of 9 + 10 will be one less. Thus, 9 + 10 = 19. Practice solving different number sentences together.
Doubles facts can also be used to solve subtraction problems. Review that fact families are number sentences that use the same numbers and opposite operations, such as 2 + 3 = 5, 3 + 2 = 5, 5 – 2 = 3, and 5 – 3 = 2. Write down 4 + 4 = 8 and have your children find its related fact: 8 – 4 = 4. We recommend using number triangles to help your children visualize how the numbers and operations are related. Then challenge them to find the difference of 18 – 9. Help your young learners understand that if they know 9 + 9 = 18, then they know that 18 – 9 = 9. They are related facts.
Empower children with different strategies to help them solve tricky math problems. Help them understand that there are often different ways to solve a problem. They can use the facts that they already know and apply them as they approach new problems.
