Calendar systems

A bit of science and history in this learning, as well as a spattering of languages (te reo and latin). We looked at different calendar systems and how they are based either on a solar calendar system (based around the length of the time the earth takes to go around the sun) or a lunar calendar that tracks the phases of the moon. Some calendars are lunisolar calendars that take both into account.

We looked at ancient calendars such as the Maramataka or Maori calendar, and alongside that looked at te reo for days of the week and months of the year, noting both transliterations or loan words from English words - Mane (Monday), Turei (Tuesday) etc, and the maori  words - Rāhina (Monday), Rātū (Tuesday) etc.

The Calendar most used by Western civilsations these days is based on the Gregorian calendar, which came from the ancient Roman Julian calendar. It's interesting to see how many names of the months are derived from the Julian calendar. We also looked at how the Romans changed the calendar to try to get it to line up with the seasons each year, and then changed the names of a couple of months to include July (after Julius Caesar) and August (after Caesar Augustus). I think it was eye-opening for some to see how our systems today date back so far. 



We looked at the reason for calendar systems (usually so people could keep track of seasons etc which influenced planting and harvesting. And we thought about the reason for a leap year, as this year is one. This goes back to the length of time the earth takes to orbit the sun, which is 365.25 days, so every 4 years we need an extra day to make the time up and get the calendar in balance again. 

This is an enormous topic and we really just got a small taste so that children could see the complexity and origins of some systems. This was also a good one to look at reasons for some systems and how they can help keep order. There are some good videos online about this topic, such as this one about leap years from Ted Ed.