1st Grade Addition Within 20 Test Solutions and Scoring (PDF)
This addition within 20 test answers for 1st Grade covers addition within 20 (Common Core 1.OA.A.1, 1.OA.B.3, 1.OA.C.6, 1.OA.C.5), with a free PDF to print.
This answer key shows each solution and how many points each part earns. Give full credit when the sentence and the sum are both correct. Give partial credit for a correct method with a small counting slip.
Grade 1 · Common Core State Standards: 1.OA.A.1, 1.OA.B.3, 1.OA.C.6, 1.OA.C.5
Addition within 20 test answers: worked solutions
Question 1 – Count and add [2 pts]
- \(7 + 5 = 12\).
- The sum is 12.
Scoring: 1 point for a correct addition sentence. 1 point for the sum 12.
Question 2 – Quick facts [3 pts]
- \(9 + 7 = 16\). The sum is 16.
- \(5 + 0 = 5\). The sum is 5.
- \(6 + 6 = 12\). The sum is 12.
Scoring: 1 point for each correct sum.
Question 3 – Hop on the number line [2 pts]
- \(9 + 5 = 14\).
- The hop ends at 14.
Scoring: 1 point for the sentence 9 + 5 = 14. 1 point for the endpoint 14.
Question 4 – Flip the addends [2 pts]
- \(9 + 6\).
- \(9 + 6 = 15\), so the sum is 15.
Scoring: 1 point for 9 + 6. 1 point for the sum 15.
Question 5 – Three numbers [3 pts]
- 3 and 7 make 10. \(10 + 9 = 19\). The sum is 19.
- 5 and 5 make 10. \(8 + 10 = 18\). The sum is 18.
Scoring: part a: 1 point for a correct method and 1 point for 19. Part b: 1 point for 18.
Question 6 – Compare [2 pts]
- \(7 + 6 = 13\), \(8 + 4 = 12\). \(7 + 6 > 8 + 4\).
- \(9 + 3 = 12\), \(6 + 6 = 12\). \(9 + 3 = 6 + 6\).
Scoring: 1 point for each correct symbol (> then =).
Question 7 – Bead story [3 pts]
\(8 + 6 = 14\). Aisha has 14 beads.
Scoring: 1 point for adding the two numbers. 1 point for the sentence 8 + 6 = 14. 1 point for the answer 14 beads.
Question 8 – Fill the frame [3 pts]
- 2 counters move.
- 7 – 2 = 5 is left. \(10 + 5\).
- \(8 + 7 = 15\). The sum is 15.
Scoring: 1 point for each correct part.
Total score
20 points
Key facts behind this addition within 20 test answers
- The sum is the total. In 5 + 3 = 8, the sum is 8.
- Counting on: start at the bigger number and count up the smaller one.
- Make a ten: 8 + 5 = 10 + 3 = 13.
- Doubles help: 6 + 6 = 12, so 6 + 7 = 13.
- Order does not matter, and adding 0 leaves a number the same.
How to use this addition within 20 test answers
Score your test with the point values shown for each question. Then read the worked solution of every question where you lost points and note the method to review.
All Grade 1 chapters: Grade 1 math.
