Make a Ten to Add — Addition Within 20 (Grade 1)

About this activity

For a sum like 8 + 5, children break the second number on a number bond so one part fills the first up to ten (8 + 2 = 10), then add what is left (10 + 3 = 13). This make-a-ten strategy comes to life in an interactive Grade 1 math activity that plays right in the browser with no account.

The big idea is to turn a tricky fact into an easy one: get to a friendly ten, then add the leftover. The child taps to fill the make-a-ten part of the bond, and the bond shows exactly how the second number splits — so the strategy is something they see and do, not something they memorize.

It is aligned to Common Core 1.OA.C.6 — adding within 20 using the make-a-ten strategy. No timer, no score — just calm, playful practice.

What's inside this activity

• Designed for Grade 1 learners (ages about 6–7)
• Common Core strand: Operations & Algebraic Thinking
• Aligned to Common Core standard 1.OA.C.6

How to play

Look at a sum like 8 + 5 shown on a number bond.

Tap to fill the part that makes a ten with the first number, then add what is left.

Not quite? Try again as many times as you like — there is no timer and no score.

What your child practices

• Break a number into two parts on a number bond
• Fill the first number up to a ten (8 + 2 = 10)
• Add the leftover part to the ten to finish (10 + 3 = 13)
• Build fluent, flexible addition within 20

Learning goals

Add within 20 using the make-a-ten strategy — the focus of Common Core 1.OA.C.6

Break a number apart to make a friendly ten

Add flexibly instead of counting every number one by one