Where's the Point? - 3

Grade 3 Mathematics Routine

Where's the Point?

Standards for Mathematical Practice (SMP)  #2, 3, and 4

This routine helps students to understand the relationships between numbers and the relative magnitude of numbers. Students will use a number line to explore these concepts.  

DIRECTIONS:

1.  Students need to move to the front of the room.  Some students may need a calculator or 100 chart for this routine.

2.  Present a number line with the endpoints labeled. Ensure that number choices are within the scope of the grade-level curriculum.

3.  Ask students to think independently about the relationship of the numbers to the unknown value of the point.

4.  After students have found the value, ask them to turn and talk and share their solution and reasoning with a partner.

5.  Bring the class back together.  Solicit and record possible solutions.

6. Have student share their reasoning and justify their answers.

7.  Ask the following questions to prompt students to share their thinking.

• • How did you find the value of the point?
  • What was half the distance between the endpoint values?
  • Were there other relationships that helped you to determine the point?
  • How did you find the value on the second/third number line (this question is if you present more than one number line at a time)?
  • Did one number line help you to determine the value on the other number lines (this question is if you present more than one number line at a time)?

VIDEO GRADE 3: 

Notice that the teacher asked the students what did they notice about the endpoints and provided wait time. The teacher asked the students if they were ready to discuss by giving her a thumbs up. She elicited a response and asked for the student to explain her response. She asked if students agreed and the student then readjusted her number and the class discussed the reasonableness of the number. The teacher acquired multiple student responses. Next, she had a student identify the midpoint and she labeled the midpoint on the number line. Notice that there was a rich discussion about what would be reasonable answers and what some unreasonable answers would be and why. After discussing the second and third number lines, the teacher repeated when one of the students made a connection between the number lines.

GOOGLE SLIDES: Where's the Point? Links to an external site.

These slides include identifying numbers on a number line up to 1,000. There are also slides for students to identify a fraction as the unknown value. Additionally, there is a template at the end to create your own endpoints.