# Addition and Subtraction within 100 Rubric

## Task

Students present a labelled model or report on addition and subtraction within 100.

## Curriculum alignment

Students investigate addition and subtraction within 100 ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)). The rubric assesses:

- Recall and application of addition and subtraction number facts and strategies ([Skills](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29852))
- Understanding that a sum can be composed in multiple ways ([Understanding](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29847))
- Understanding that addition and subtraction represent quantities or lengths ([Understanding](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29851))
- Ability to verify sums or differences using inverse operations ([Skills](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29852))

## Rubric

| Criterion | Beginning | Developing | Proficient | Exemplary |
|---|---|---|---|---|
| **Accuracy of calculation** | Calculations contain multiple errors. Sums or differences are incorrect. | Most calculations are correct, but one or two errors appear. | All calculations are correct within 100. | All calculations are correct and shown with clear working. |
| **Use of strategy** | No clear strategy is shown. Student guesses or counts on fingers. | One strategy is attempted but applied inconsistently. | Student applies one appropriate strategy (doubles, making tens, or inverse operations) correctly. | Student applies multiple strategies and explains why each works. |
| **Labels and model clarity** | Model is missing or unlabelled. It is hard to follow. | Model is present but labels are incomplete or unclear. | Model is clear and all parts are labelled with numbers and operation symbols. | Model is clear, detailed, and labelled. Visual representation matches the calculation exactly. |
| **Composition of sums** | Student shows only one way to make a sum. | Student shows two ways to compose a sum. | Student shows at least two different ways to compose the same sum. | Student shows three or more ways to compose a sum and explains the pattern. |

## Scoring

Add the level points for each criterion: Beginning = 1, Developing = 2, Proficient = 3, Exemplary = 4.

- 4 to 5 points: Beginning
- 6 to 9 points: Developing
- 10 to 13 points: Proficient
- 14 to 16 points: Exemplary

## Notes for the teacher

- Look for evidence of strategy, not just correct answers. A student who counts on but arrives at the right sum is developing; a student who uses making tens is proficient.
- Labels must include numbers and operation symbols (+ or −). A model without labels cannot be marked higher than Developing.
- When assessing composition of sums, accept any representation: tens and ones blocks, number lines, drawings, or equations. The key is showing different ways to reach the same total.
- If a student verifies their work using the inverse operation (for example, checking 24 + 15 = 39 by doing 39 − 15 = 24), mark the accuracy and strategy criteria at Proficient or Exemplary.

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*AILI marking guide · language en · model claude-haiku-4-5-20251001 · generated 2026-09-17 · id a3368c8c-758a-4a96-881a-eb06bb8d7ca0*

### Sources

- node:n1: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29843)
- node:n2: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)
- node:n3: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)
- node:n4: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29848)
- node:n5: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29847)
- node:n6: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29850)
- node:n7: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29852)
- node:n8: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29851)
- node:n9: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29852)
- node:n10: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29850)
- node:n11: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29848)
- node:n12: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29844)
- node:n13: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29847)
- node:n14: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29851)
- node:n15: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. › How can addition and subtraction be interpreted? › Students investigate addition and subtraction within 100. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29846)
- node:n16: Mathematics › Mathematics (K–6) › Grade 2 › Number: Quantity is measured with numbers that enable counting, labelling, comparing, and operating. (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/29843)