This grade 3 add test answer key gives the full solution and the scoring guide for each of the 9 test questions on adding and subtracting within 1,000.
Use this key to score the test out of 20 points. Each solution shows the work a student should write, and the scoring note explains how to give partial credit when a student shows correct steps but makes a small slip.
Grade 3 Add Test Answer Key: questions 1–5
Question 1: Two sums (2 points)
- \(274 + 358 = 632\). 632
- \(496 + 305 = 801\). 801
Scoring: 1 point for each correct sum.
Question 2: Two differences (2 points)
- \(683 – 251 = 432\). 432
- \(702 – 385 = 317\). 317
Scoring: 1 point for each correct difference.
Question 3: Blocks (2 points)
The blocks show 235 and 148. \(235 + 148 = 383\).
383
Scoring: 1 point for the correct addition sentence, 1 point for the correct total.
Question 4: Number line (2 points)
\(350 + 300 = 650\), then \(650 + 40 = 690\). The sentence is \(350 + 340 = 690\).
690
Scoring: 1 point for the addition sentence, 1 point for 690.
Question 5: Estimate and solve (2 points)
- \(400 + 400 = 800\). 800
- \(389 + 412 = 801\). 801
Scoring: 1 point for a rounded estimate of 800, 1 point for the exact sum.
Grade 3 Add Test Answer Key: questions 6–9
Question 6: Missing numbers (2 points)
- \(500 – 267 = 233\). 233
- \(276 + 134 = 410\). 410
Scoring: 1 point for each correct missing number.
Question 7: Library shelves (2 points)
\(428 + 359 = 787\).
787 books
Scoring: 1 point for a correct equation, 1 point for 787 books.
Question 8: Field trip (3 points)
- \(278 + 195 = 473\). 473 students
- \(645 – 473 = 172\). 172 students
- \(172 + 473 = 645\), which is the total number of students. The answer checks.
Scoring: 1 point for each part.
Question 9: Find the mistake (3 points)
- In the ones place, 3 is less than 8, so Noah must regroup. He cannot swap the digits to make the subtraction easier.
- Regroup: 503 is 4 hundreds, 9 tens, 13 ones. Ones: \(13 – 8 = 5\). Tens: \(9 – 4 = 5\). Hundreds: \(4 – 2 = 2\). 255
- \(255 + 248 = 503\). The answer checks.
Scoring: 1 point for explaining that the digits must be regrouped, 1 point for 255, 1 point for a correct check.
Scoring summary
20 points: add the points of every question of this grade 3 add test answer key.
How to use this grade 3 add test answer key
Use this grade 3 add test answer key to score the test fairly and to see which skills need more practice.
Printable PDF · Test Answer Key
Grade 3 Adding and Subtracting Within 1,000 test answer key
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