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Lesson 9: Spaghetti Line

Lesson 9: The Spaghetti Line


Students will estimate the line of best fit for a height and arm span dataset using a strand of spaghetti as a modeling tool.


  1. The Spaghetti Line handout (LMR_4.10_The Spaghetti Line)

    Note: Advance preparation is required. Cut out plots prior to beginning the lesson.

  2. 1 lb. of Uncooked Spaghetti

  3. Grid Paper

  4. Tape or Glue

  5. Poster paper


line of best fit

Essential Concepts:

Essential Concepts:

We can often use a straight line to summarize a trend. “Eyeballing” a straight line to a scatterplot is one way to do this.


Note: Lab 4A may be done in the same class period as this lesson.

  1. Inform students that in this lesson, they will estimate the equation of the line of best fit for a height and arm span dataset.

  2. Distribute The Spaghetti Line handout(LMR_4.10_The Spaghetti Line) to each student and a couple of spaghetti strands per team. Students will estimate the line of best fit as outlined in the handout. Team solutions should be recorded on poster paper. They will glue their assigned plot on the poster and record their responses to the questions on the poster paper.

    Note to teacher: If necessary, review how to find the slope of a line using two points and how to write an equation using the slope and y-intercept.

  3. Ask teams to post their work around the room. Conduct a Gallery Walk so that teams can see each other’s work.

  4. Lead a discussion about the teams’ lines. Ask: Which team has the best line? Why?

    Note to teacher: Push the students a bit by adding an obviously bad line to the graph and asking why their line is better than this one. Push them to come to an understanding that the “best” line comes close to the most points and this line is called the line of best fit..

Class Scribes:

One team of students will give a brief talk to discuss what they think the 3 most important topics of the day were.

Homework & Next Day

LAB 4A: If the Line Fits...

Complete Lab 4A prior to Lesson 10.