Addition Within 20: Grade 1 Math Worksheet – PDF Download

Grade 1 Addition Within 20 Worksheet: problems 1–5

Problem 1: Count and add

Maya has 5 blue counters and 3 orange counters. Write an addition sentence for the picture.

Problem 2: Ten frame sentence

Write an addition sentence for the ten frame.

Problem 3: Find the sums

Find each sum.

1. \(6+2\)
2. \(7+3\)
3. \(9+0\)
4. \(4+5\)

Problem 4: Small doubles

Find each double.

1. \(2+2\)
2. \(3+3\)
3. \(4+4\)
4. \(5+5\)

Problem 5: Count on with a number line

Start at 5. Hop 4 times to find \(5+4\). Write the sum.

Grade 1 Addition Within 20 Worksheet: problems 6–10

Problem 6: Count on from the bigger number

Find \(3+8\) by starting at the bigger number and counting on.

Problem 7: Show a double

Write the double shown by the ten frames.

Problem 8: Near doubles

Use a double to help. Find each sum.

1. \(7+8\)
2. \(6+7\)

Problem 9: Make a ten with frames

Jamal has 9 blue counters and 4 orange counters. Write the sum of \(9+4\).

Problem 10: Make a ten with numbers

Fill in the missing numbers: \(8+6=8+2+\text{ __ }=10+\text{ __ }=\text{ __ }\)

Grade 1 Addition Within 20 Worksheet: problems 11–15

Problem 11: Switch the order

Sofia says \(3+9=12\). Write the same numbers in the other order and give the sum.

Problem 12: Circle the twelves

Circle the addition sentences that equal 12: \(6+6\), \(7+4\), \(8+4\), \(9+2\).

Problem 13: Three numbers

Find \(2+7+3\).

Problem 14: Three numbers again

Find \(4+6+5\).

Problem 15: Two sentences

Use the numbers 8, 5, and 13 to write two different addition sentences.

Grade 1 Addition Within 20 Worksheet: problems 16–20

Problem 16: Mixed sums

Find each sum.

1. \(9+9\)
2. \(10+7\)
3. \(8+9\)
4. \(7+7\)

Problem 17: Cookies at the bake sale

Sofia sold 8 cookies in the morning. She sold 5 more cookies in the afternoon. How many cookies did she sell in all?

Problem 18: Balloons

There are 7 red balloons and 6 blue balloons. How many balloons are there in all?

Problem 19: Missing stickers

Jamal had 9 stickers. He got some more stickers. Now he has 14 stickers. How many stickers did he get?

Problem 20: Zoo animals

At the zoo, Liam saw 5 monkeys, 4 zebras, and 6 lions. How many animals did he see in all?

Grade 1 Addition Within 20 Worksheet: problems 21–22

Problem 21: Ducks in the pond

Some ducks were in the pond. Then 6 more ducks swam in. Now there are 13 ducks. How many ducks were there at first?

Problem 22: Pages read this week

Diego read 6 pages on Monday, 7 pages on Tuesday, and 5 pages on Wednesday. How many pages did he read in all?

How to use this grade 1 addition within 20 worksheet

Print this grade 1 addition within 20 worksheet as a PDF, solve every problem on paper, then compare with the answer key.

See every chapter on the Grade 1 math page.