Science Lesson on Calendars

Happy New Year, everyone! The start of a new year is a good time to consider how and why we use the calendar we do. Here's a link to science teacher David Stern's interesting lesson plan focused on various calendars and how they worked for different populations of people.

The learning objectives for this lesson follow:

  • "The differences between solar day, sidereal day and mean solar day, and what each is used for.
  • The differences between the solar year, the Julian calendar and the Gregorian calendar.
  • About the Moon cycle ("synodic period"), the orbital period of the Moon, and the reason they differ.
  • About the Metonic calendar (used by Jews and Chinese) and the Moslem one, in both of which "one month" extends through one full cycle of the Moon.
  • About the Persian calendar, where the new year always begins at the spring equinox.
  • Some facts about the calendar of the Maya culture, which thrived in Mesoamerica before Columbus. Also about the Ethiopian calendar, where every month has 30 days, and the remaining 5 or 6 days form a short "13th month."

Let us know your thoughts, especially if you draw upon any of these ideas for a lesson.

Cheers, Susan Finn Miller

Moderator, Teaching & Learning CoP