The Digital Divide: A Data Analysis Activity Using Subtotals

Maryann S. Allen
Colby-Sawyer College, New London, NH
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This material is replicated on a number of sites as part of the SERC Pedagogic Service Project


In this Spreadsheet Across the Curriculum activity, students will use Excel to explore the digital divide within the United States. Students will be given data from the US Census as an embedded spreadsheet and asked to analyze it. They will be introduced to the subtotal tool in Excel and will use it as a data analysis tool on the US Census data. Students will also be taught about weighted averages by the use of spreadsheets in Excel. When finished, students will learn the value of Excel when calculating large data sets.

Learning Goals

Students will:
  • Download data from an embedded Excel file and develop a spreadsheet.
  • Use the spreadsheet to calculate rates.
  • Use the spreadsheet to calculate weighted averages.
  • Use the Subtotal function.
In the process the students will:
  • Gain knowledge of entering equations in Excel spreadsheets.
  • Understand the meaning and importance of weighted averages.
  • Understand how errors can be avoided when calculating averages.
  • Analyze digital divide data from various regions in the United States.

Context for Use

This module was designed for use in an introductory computer class for first-year college students. It could also be easily adapted for use in a secondary-education computer course.

Description and Teaching Materials

The module is a PowerPoint presentation with embedded spreadsheets. If the embedded spreadsheets are not visible, save the PowerPoint file to disk and open it from there.

The above PowerPoint files are the student version of the module. An instructor version is available by request. The instructor version includes the completed spreadsheet. Send your request to Len Vacher ( by filling out and submitting the Instructor Module Request Form.

Teaching Notes and Tips

This activity can be used as an independent homework assignment, or as an in-class activity where the use of the Subtotals tool is led by the instructor. The activity takes approximately 45 minutes to complete, with additional time needed to answer the End of Module Questions.


The student version of the module includes an end-of-module assignment that can be used for assessment. The instructor version also includes a pretest that can be coupled with the end-of-module assignment.

References and Resources