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Activity 1: Chart the Sun
Activity 2: Build a Sundial
Quizzes
Activity 2

Build a Sundial 
The Egyptians told time by the Sun using a sundial. Over the course of a sunny day, your students can make their own sundial.
  • Take a large piece of posterboard in a light color outside, along with a compass. Find due north.
  • Fix the posterboard to the ground, using weights or stakes; the paper must not move the whole day.
  • Draw an arrow to the side of the paper indicating the direction of north.
  • Stick a pencil or similar long stick in the middle of the paper. The formal name for this stick is a "gnomon," and it will cast a shadow on the paper.
  • Each hour on the hour, go outside and use a ruler to draw a line that corresponds to the shadow cast by the gnomon. Write the time beside this line.
By the end of the day you should have a series of lines spread out like a fan. Each time the sundial is used, it must be lined up with due north! It may not tell the time exactly right over the course of the year because the Sun shifts position, and it will be less accurate the farther north you live, but the readings should be close. The Egyptians didn't need to measure time as exactly as we do!