Hypatia

Curriculum Goal

Junior: Geometry and Spatial Sense

• Explain how protractors work, use them to measure and construct angles up to 180°, and use benchmark angles to estimate the size of other angles.

Context

• Whole-class introduction followed by pair-based exploratory activity.

Materials

• History of Hypatia (Appendix A)
• Astrolabe drawing (Appendix B, to print on card stock)
• Astronomical object cut-outs (Appendix C)
• Recording sheet (Appendix D)
• Hole punch
• String (30cm)
• Weight
• Tape
• Scissors
• Straw

Lesson

• Provide a brief history of Hypatia.
• Invite students to construct their own astrolabes (detailed instructions).
• Cut out the astrolabe drawing and punch a hole as indicated.
• Cut a piece of string (~ 30cm long). Knot one end to the hole on the astrolabe and attach a weight to the other end.
• Tape a straw on the edge indicated.
• Instruct students on its use:
• Hold the astrolabe so the curved part is downwards, and the 0° mark is closest to you.
• Look along the flat edge of the astrolabe with your eye looking through the straw.
• Point the straw at the object that you want to measure. As you tilt the astrolabe up, the weight will move to measure the degree of your angle of observation.
• Place astronomic object cut-outs on the classroom walls and have students measure the angles of observation with a partner. Invite them to find different objects and record their angles of observation.
• Gather for a group discussion.
Example prompts:
• What happens when you hold your astrolabe and look straight up?
• What happens when you look straight ahead?
• Does it make a difference if you measure the angle while lying down compared to if you were sitting or standing?

Look Fors

• Can students accurately measure angels up to 180° using the astrolabe?
• Do students see the similarities and differences between using an astrolabe and a protractor?