Education Technology

Watching Your Weight

Published on 06/09/2008

Activity Overview

In this activity, students examine how moving a weight up along a board affects the downward force on the board. They explore how children with different weights can be balanced on a seesaw.

Before the Activity

  • Position the scale and the block far enough apart so that the wooden plank is supported on one end by the scale and the other end by the block
  • Starting at the edge of the scale, place marks at 10-cm increments on the wooden plank
  • Set up the calculator for data collection using the procedure described in the attached Appendix PDF file
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 25 - 37 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Place books at the 0 cm mark on the plank and record the weight
  • Move the books to the 10 cm mark and record the weight
  • Continue to move the books away from the scale in 10-cm increments and record weights
  • Enter the data of distance and weight as a list
  • Use this data to graph a scatter plot
  • Visually estimate the trend line and find the line that contains as many points as possible
  • Determine an equation for a trend line for the data, calculate the slope, and graph the trend line
  • Find the weight of objects placed at different distances from the scale
  • Find the distance from the scale given the object's weight shown on the scale


  • Find a linear equation for the data
  • View the graph of the best fit line
  • Use the linear regression model, find weights at different distances, and find the distance given the weight
  • After the Activity

    Students will complete the Data Collection and Analysis page and answer questions.

    Review student results:

  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary