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Grade 2 · unit review

Review: Measure Standard Lengths and Number-Line Changes

Read ruler intervals, compare unit sizes, find differences, and model changes on a line.

Download reviews and answer keys

Bring the unit skills together

Use these 4 new cases to check your reasoning. Choices are temporary and are not saved to an account, sent to staff or recorded as school grades. Download your current review choices before leaving or reloading.

Unit review questions
1. A strip begins at 6 cm and ends at 20 cm. What is its length in centimeters?
Need a hint?
  • Count spaces between marks, not both endpoint labels.
  • The end label equals length only when the start is zero.
2. One long unit equals three short units. A strip measures 8 long units. How many short units is that?
Need a hint?
  • Convert to one common unit before comparing.
  • A smaller written count may describe a longer unit.
3. A ribbon is 38 cm and a strip is 21 cm. How much longer is the ribbon, in centimeters?
Need a hint?
  • Write centimeters beside both inputs and the result.
  • How much longer requests a difference, not a combined length.
4. Start at 43 on a number line and move left 14. What is the endpoint?
Need a hint?
  • Use equal intervals on the line.
  • Subtraction moves left on a usual increasing number line.

The download contains your current choices and any checked feedback. Keep the separate transfer-task work in your own document; downloading its instructions does not mark it complete.

Use the skills in a new task

A strip begins at 3 cm and ends at 15 cm on a ruler. Show its length and a number-line jump of that length.

Work on paper or in your own document. Explain the choices you made.

  • Draw or label the numbers or shape features the task gives you.
  • Say why each calculation or shape choice follows the ideas in this unit.
  • Check that your answer fits the story or drawing in the task.
Compare with a model response

The strip length is 15−3=12 cm. A jump from 3 to 15 also covers twelve one-centimeter intervals, not fifteen.

A different response can also meet the criteria. Compare the evidence and reasoning, rather than copying the wording.