3.NF.A.2 Represent a Fraction on a Number Line

Evidence Statement 3.C.6-1 Base explanations/reasoning on a number line diagram (whether provided in the prompt or constructed by the student in the response)

Running Miles

Part A

Alexandro ran 7/2 miles.

• Plot how far Alexandro ran on the number line below.

This image shows a number line with the intervals zero through four marked. One-half is marked between the zero and one.

Haley ran 9/3 miles.

• Plot how far Haley ran on the number line below.

This image shows a number line with the intervals zero through four marked. One-half is marked between the zero and one.

Part B

Use the number lines above to explain who ran farther.

Write your explanation and answer in the space provided.

Student Copy

Scoring Rubric Part A

Score 2

Student response includes the following elements.

• The student provides correctly plotted Alexandro’s distance on the number line.(   7/2  is plotted at "3 1/2"  point on the number line)

   

• The student correctly plotted Haley’s distance on the number line.   ( 9/3  is plotted at the “3” on the number line)

   

Score 1

Student response includes one of the elements.

Score 0

Student response is incorrect.

Scoring Rubric Part B

Score 2

Student response includes the following elements.

Reasoning Component = 2 points

• The student correctly identifies who ran farther, (Alexandro)
• The student provides a valid explanation using the number lines.

Student Sample Response: Alexandro ran farther because 7/2 is placed on the number line at  3 ½ . I counted 2/2 equal 1, 4/2= 2, 6/2= 3 and I had one ½ left over so I marked the number like at 3 ½.  Haley’s distance was 9/3. Three thirds equal 1 whole so on the number line  I count 3/3= 1, 6/3=2, and 9/3= 3. So I put a dot on the 3  Alexandro’s mark was at 3 ½ and Hanleys was a 3. 3 ½ is further than 3 so Alexandro ran farther.

OR other explanations that include a valid method to explain how to use the number line to decide which person ran further.

Score 1

Student response includes one of the elements.

Score 0

Student response is incorrect.