Education Technology

Now You See It, Now You Don't

Published on 06/09/2008

Activity Overview

In this activity, students' study the relationship between age and near point accommodation (NPA). They predict a person's age using NPA distance values. They use exponential regression, create box-and-whisker plots and histograms.

Before the Activity

  • 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 87 - 96 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Measure the closest distance between the eye and the paper when the letter on the paper remains in focus (NPA)
  • Record the age, and the distance between the eye and the paper
  • Repeat the procedure with 4 different subjects
  • Enter the age and NPA data for subjects in three different age groups as lists
  • Group the data for different age groups
  • Create a box-and-whisker plot to analyze the data
  • Find the median near point accommodation of the three age groups analyzed
  • Observe that higher the age the greater the width of the box plot
  • Use the graph of the exponential regression to determine the person's age based on his NPA distance
  • 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