Lesson Focus: Leap Year

We've all experienced a Leap Year before. Heck, we all even learned a rhyme in elementary school about it. But, understanding why we have a leap year and when it will occur is important when attempting to explain it to young minds.

Remember the days of the month rhyme:
30 days hath September,
April, June and November.
All the rest have 31,
excepting February has 28.
Leap Year comes just in time,
to give February 29.

Even as little kids we know that February is the shortest month, and that sometimes it has an extra day.

When Do Leap Years Occur?
We've all been told that Leap Years occur every 4 years, but this isn't entirely accurate. In order for a year to become a Leap Year it must satisfy 3 criterion:
1. Every year that is divisible by 4 is a leap year.
2. Of the years in #1, if a year can be divided by 100 than it is NOT a leap year.
3. Of those discounted by #2, then it IS qualified to be a leap year.

So, this means the years 1800, 1900, 2000, 2100, 2200, 2300, 2400 and 2500 are NOT leap years based on the #2 qualifier. BUT, the years 2000 and 2400 will be added back in as the acceptable leap years because of the #3 qualifier - Significantly, the year 2000 was the first time in history we used the 3rd qualifier to keep a leap year...

All those qualifiers are great for the older child or adult looking to understand what makes a year a leap year. But it doesn't really tell us WHY?

Why Do We Need Leap Years?
Well it all comes down to astronomy. A year is supposed to represent the amount of time the earth takes to make a complete circuit around the sun. One of the problems with this is the Earth doesn't make a true circle around the sun, but more of an elliptical pattern.

Here's the scientific explanation for the older child / adult:
The Vernal Equinox is when the Sun is directly above the equator - thus causing night time and day time to be equal. The length of time from Vernal Equinox to Vernal Equinox (successively) is called the Tropical Year, or Solar Year. It equals 365.2422 days. (Incidentally the vernal Equinox is the origin of Easter, falling on March 21, more on this coming in another article.) The Gregorian Calendar - the one used by the majority of people on the planet - measures 365 days. This means we have a loss of 0.2422 days each year (or about 6 hours/year).

After 100 years that's a loss of 24 days, and would mean we would be almost an entire month ahead of the vernal equinox season - imagine the significance for farming. The vernal equinox is this indicator of Spring. Generally farmers would spend this time frantically repairing and preparing farming equipment or the first major planting. But, without those 24 days, March's weather would be that of February, with the shift getting worse and worse with each decade that passes.

The desire, then, is to align the calendar to match the seasons. Therefore approximately every 4 years, we make the adjustment, making the error as insignificant as possible. Ironically there is no perfect calendar used on the planet - even the Gregorian calendar we use, will eventually mean the loss of a day (every 3236 years) but it is the closest to aligning the seasons and our days.

Explaining Years and Days to Young Children.

It would be impossible to explain a Leap Year without first helping your child understand the concepts involved - namely the years, days and orbit. Believe it or not, this is actually quite east to help a child see. I do this experiment with my boys for fun, it's also a great way of explaining the Equinoxes and other astrological important effects.

Supplies: 1 styro-foam ball (like the kind you can buy at a craft store), 1 straw, masking tape, 1 lamp, 1 push pin, 1 Fine Tipped Marker

Procedure:
1. Place the lamp in the middle of the floor and remove it's shade - so the bulb is naked.
2. Around the lamp make a large oval on the floor with your masking tape (this represents the earth's orbit)
3. Press the straw through the ball at an angle (this is the earth's angle) My children like to paint the earth first to make it more realistic.
4. One of the children stands on the masking tape oval. Holding the earth by the two ends of the straw.
5. First I have the child twist the straws which will cause the earth to spin in place - represents a day, I'll often put a push-pin in to represent us on the earth so they can further see how the earth's rotation effects daylight and night time.
6. Draw a circle around the middle of the ball to represent the equator.
6. Have the child walk around the taped circle to find the point where the 'sun' (or lamp) is lined up with the 'equator'. This represents the Vernal Equinox - when the day light and night time are equals.
7. From this point we walk the circle, trying to rotate the Earth on it's axis at he same time to count the days - it doesn't need to be accurate equaling the 365 days in a year, we're just trying to demonstrate how as the Earth moves around the sun, it's also spinning going from day to night, while the motion around the sun is responsible for the seasons.

Now that your child has a better idea of how the earth moves around the sun - you can pull out a calender. Show him his birthday or Christmas/Yule - these are days even the youngest of children will recognize. Flip through the calender explaining this is another way of demonstrating the 365 days it takes the Earth to go around the sun....BUT WAIT! It does not take exactly 365 days, there's some time left over. Like how it doesn't always take the same amount of time to get to the park. If we didn't fix the calendar then that little bit of time would add up and up...until after many many years - it would take Longer than 365 days to get from Christmas to Christmas. (Oh The Horror!)

Books For Children With Leap Year Themes:

*My Birthday...Finally! On Saturday Miles will be celebrating his birthday. Although he is happy about his birthday there seems to be some confusion about how old Miles will be. Will he be eight or will he be just two? [You can also purchase an accompanying workbook from Amazon.com] Written By, Michelle Whiticker Winfrey recommended for ages 9-12; published by Hobby House Publishing Group (July 1, 2007)

*Leopold's Long Awaited Leap Year Birthday: Leopold's and his parents wait patiently for his first birthday - February the 29th - to arrive, but it just never seems to come. Finally, the wise old doctor figures out why the seasons continue to pass without any recognition of his special day...Mother explains it's as a "Peek-a-boo Holiday"... Written By, Dawn Desjardins; illustrated by, C.E. Locander

*The Leap Year Book: This is the most comprehensive book on the subject yet. From Legends and Folklore, to all about Leap Year cards and postcards from the early 1900's. Significant events that happened in a Leap Year as well as people born on Leap Day. There is even a picture of Raenell on page 60 (she was born in 1960) where the Honor Society of Leap Day Babies is mentioned. Written By Barbara Sutton-Smith, published by, Fitzhenry and Whiteside; 1 edition (January 10, 2000

*The Pirates of Penzance: When Frederic was yet a little boy, his nurse (Ruth) was told to apprentice him to become a pilot. She heard the word incorrectly and apprenticed him to a band of pirates, remaining with them herself as a maid-of-all-work. Although Frederic loathed the trade to which he had thus been bound, he dutifully served and, as the curtain rises, his indentures are almost up and her is preparing to leave the band and devote himself to the extermination of piracy. His indentures were to run until his twenty-first birthday, and - as he was born on February 29 - he has really has as yet only five birthdays. Obeying the dictates of his strong sense of duty, he immediately rejoins the pirates."
From the G. Schirmer, Inc. version of Pirates of Penzance by Gilbert and Sullivan.

Leap Year Folklore, Tid-Bits & History

* A person born on February 29th, say's they were born on Leap Day - as it is impossible to be born on an entire year - so they call themselves Leap Day Babies!
* "Hello, Sir, Will you marry me?" - Women were allowed to propose to men on this day. It is believed this derived from the story of St Brigit who struck a deal with St Patrick that would allow women to propose to men every four years - Brigit complained to St Patrick that her female followers were upset that they never had the chance to exert control and propose (ancient Celtic women had a lot more power than other ancient societies). St. Patrick proposed women be allowed the right every 7 years - which wasn't good enough for Brigit who counter offered with every 4 years. Patrick thought this demonstrated how subservient women were and was therefore surprised when Brigit turned around and proposed to him! He declined with the promise of a kiss and a new silk gown.So it became an unwritten law in the Middle Ages that the men who refused the honor would compensate the woman with a kiss and a pair of gloves or a dress - to give the men a little warning, women who were to propose would allow a little bit of a red peti-coat to peak from beneath their gown. Apparently there was even a 1288 law by Queen Katheryn of Scotland that placed taxes on a man who proposed on this day. The tradition has come so far as to jokingly be referred to as Sadie Hawkins day, after a character in the Al Capp cartoon strip Li'l Abner, who chased after her man.
* Bachelor's Day - there is another tradition, after the 19th century when the above ran out of steam, where women were allowed to propose any day of the entire Leap Year EXCEPT for Leap Day. If the gentleman turned the lady down than he still had to compensate her - but NOT if she proposed on the Leap Day itself. So it was in effect the opposite of the first tradition.
* Leap Day is also the day of observance for St. Oswald's Day - the 10th century arch-bishop of York who died on Feb 29, 992. A feast in his honor was observed only on the Leap Days.
* February 29 is one of the days of Ayyám-i-Há (February 26 to March 1) in the Bahá'í calendar. These days are dedicated to fasting preparations, charity, hospitality and gift-giving.
*The Greeks considered it bad luck to marry on a Leap Day.
* Until 1970 The Roman Catholic Church always celebrated the Feast of St. Matthias on this day. He was the apostle chosen to replace Judas, by the other 11 apostles.

Resources:

*Leap Day -- February 29; Steffen Thorsen 1995-2008. http://www.timeanddate.com/date/leap-day-february-29.html
*Leap Year, Wickipedia Encyclopedia, http://en.wikipedia.org/wiki/Leap_year