Beacon Lesson Plan Library

How Tall is that Billboard?

Alan Kent
Highlands County Schools


This lesson covers constructing and using a basic hypsometer to measure the heights of tall objects such as trees, billboards, and buildings.


Relates the concepts of measurement to similarity and proportionality in real-world situations.


-5” x 8” index cards
-Washers, dime to nickel size
-Drinking straws (not flexible type)
-Tape measures (minimum of 25’ length)
-Scotch tape
-Basic calculators


1. Ensure that ratio and proportion, and associated computations, have been taught prior to attempting this lesson.

2. Gather the materials and have them ready to distribute along with copies of the attached file.

3. Tour the campus; pick out various objects to measure, (at least ten); calculate the heights of each so that you will have the information needed to complete the assessment.


Prior Knowledge: Students must be familiar with basic mathematical operations including basic equation solving and working with proportions.

1. Divide the class into teams of two; use whichever method works best for your situation (eg. numbering students odd/even, allowing them to pair off, etc.).

2. Have the teams construct their hypsometers, in the classroom, using the procedures on the top of page 1 of the attached file.

3. Take the students on a “field trip” on campus. Have each of them perform the measurements, utilizing the procedures on the bottom of page 1 of the attached file and recording the data on the Data Table on page 2 of the attachment. Note: Have students determine the correct height of at least ten objects.

4. Back in the classroom, have students complete filling-in the Data Table on page 2 of the attached file, utilizing the formula and procedures below the table.


Collect and check the student work on the Data Table. Most items measured should have been premeasured by you prior to the introduction of this lesson. Correct height calculations for eight of ten objects measured is considered a successful understanding of the concept of similarity and proportionality.


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