Missing Number, Subtract Within 20

Match the strategy to the numbers: count back for small numbers taken away, think addition or make ten for bigger ones. Have your child say the matching addition fact out loud, like 7 plus 5 equals 12, before writing the difference.

Find the missing number in subtraction facts within 20 by thinking of a known fact. To subtract means to take away. A box shows the missing number that makes the fact true. The directions on the page read: Think of the fact you know. Then, write the missing number in each box. The page opens with a worked example, and the answer key shows every answer.

Yes, both. We made it for 1st Grade subtraction, and the page works the same whether it lands on a kitchen table or a center rotation. At home, most families go through it together and talk the answers out loud, and that talking is where most of the learning happens with subtraction strategies. In class it runs well as independent work while you pull a small group. Print one copy or thirty, whichever the day needs.

They count back, hop left on a number line, think addition and subtract down to ten. Each strategy turns a harder fact into steps a child already knows.

For 12 - 7, a student asks what number added to 7 makes 12. Since 7 + 5 = 12, the answer is 5. The think addition sheet gives an addition box to fill in first.

Count back works best when the number taken away is small, like 1, 2 or 3. For larger numbers, think addition or making ten is usually faster. The which strategy sheet lets students practice choosing.

They support 1.OA.C.6 (subtract within 20), 1.OA.B.4 (subtraction as an unknown addend) and 1.OA.D.8 (find the missing number in a subtraction equation).

First graders should subtract within 20 using strategies like counting back, using related addition facts, and making ten (CCSS 1.OA.C.6). They should also understand the relationship between addition and subtraction and solve comparison word problems.

Use number lines and hundred charts to make subtraction visual. Practice fact families (e.g., 3+4=7, 7-4=3) to show how addition and subtraction are connected. Start with subtraction within 10 before moving to larger numbers. Consistent daily practice with worksheets builds confidence.