Education Technology

Cell Phone Range

Activity Overview

Students will learn to identify the domain and range of various real-world step functions. They will graphically explore numerical data points and observe step functions. Open and closed points on a graph are investigated and discussed.


  • Step functions, and other functions
  • Open and closed points on a graph

About the Lesson

Encourage students to summarize what they have learned from completing the activity. If desired, discuss the extension with students.