Activity 1 - Measuring angles with your hands and fingers

Students will learn how to measure angular distances in degrees using their hands and fingers as makeshift protractors.

Step by Step guide 

In this activity, students will learn how to use their hands and fingers as protractors to measure angular distances between objects in degrees. The first in-class activity will provide students with the tools they need to conduct their own experiment outside. 

Teach the students how to use their hands and fingers to measure angular distances in degrees. By holding your hand out at arm’s length, the width of your little finger is about 1°. For reference, the diameter of the Sun and Moon are about half a degree. Three fingers is about 5°, a fist is 10°, and so on.

Figure 3. Hands to measure distance. Image: Fort Worth Astronomical Society. Used with Permission.

Teacher notes: If students have seen the Disney film Moana, the teacher can discuss how Moana used a similar technique in the film. ⁰  

1. Students should develop their own mnemonic (memory aide) for remembering which hand measures what angles. 

2. Students then practice measuring angular distances (height, width, etc.) in the classroom. They can use combinations of their fingers to measure the height or width of a door, window, chalkboard, building, etc. Students nearer the object being measured will measure larger values than students further away. This will enable them to estimate, measure and compare angles using degrees, using their hands as a protractor. 

This introduces students to estimating, measuring, and comparing angles in units of degrees, using their hands and fingers as a protractor (ACMMG112).