CU2-9

2:9 **Title:** Lunar Calendar - Need and form of correction
 * Goals:** Students will learn why and how the Lunar Calendar is adjusted to be in sync with Solar Calendar and why the adjustment is in the form of an extra month every few years rather than an extra few days every year.
 * Materials:** Solar and Lunar scroll calendars. Lined paper, pencils, construction paper, crayons, Hebrew and standard calendars (enough for every two children to share one)
 * 1) **Gain the attention of the learner**. Have the students determine which year is longer by aligning the Solar and Lunar scroll calendars
 * 2) **Review relevant past learning** Jewish festivals always occur at the same time in the cycle of the moon. Several of them occur on the Full Moon when the light is brightest.
 * 3) **Present new material** Each Hebrew month begins with the appearance of the new moon. It takes 354 days for the moon to circle the earth 12 times. It takes the earth 365 days to travel around the sun. The arrival of the new month was determined by watching the moon phases. Now a fixed calendar is used in which the length of the months alternates between 29 and 30 days. The 12 month year of lunar months is 11 1/4 days less than the 12 months of the solar year. In three years, the difference is more than a month. If no adjustments are made, a spring month for sowing could shift into a winter month that kills the young plants. To correct the lunar year, 11 ¼ days could be added to each year. What would happen to phase of the moon if Sukkot was celebrate 11 days later? Since agricultural holidays are closely related to the seasons. Every two or three years, one extra month of 30 days is added to a year, called a leap year. The additional month is called Adar 2 and it occurs after Adar 1. By adding a whole month, the relation of the holidays to the phases of the moon does not change. In this way the calendar satisfies the needs of 1) keeping seasonal events in the same season which requires a solar calendar and 2) celebrating holidays during the full moon which requires a lunar calendar. In our times, the insertion tends to take place in the February/March period of the Gregorian calendar. The years 3, 6, 8, 11, 14, 17, and 19 of a 19 year cycle are leap years of 13 months each (see http://www.geocities.com/Athens/1584/#01)
 * 4) **Provide guided practice** Whole months were added to correct for the extra 11 1/4 days instead of adjusting the length of the months. What inconsistency can be observed by comparing each month’s moon phases? How could this impact on how the ancient Hebrew communities planted and marked their festivals? Why are most holidays celebrated during the full moon? What happens if the length of each month is changed or not changed? Imagine living in ancient times.
 * 5) **Provide independent practice** Refer to the monthly lunar pictures. If you depended on the light of the moon to do your most important tasks, how many days of bright light are available during the month? Imagine life in ancient times. Divide a page in half lengthwise. On the left half draw a picture showing what happens to the barley if it is planted in winter and on the other half if it is planted in early spring.
 * Close the lesson ** Students should share the pictures and add them to their Holiday Passport.