The Calendar (1963)

[Applause] [Music] just suppose that by Magic we could slow down [Music] or yes this is a trick we usually observe events in a more natural rate of time have you ever noticed how long a time it takes for day to become [Music] night it takes a much longer time for the seasons to [Music] change here is a length of time everyone knows the time from one birthday to the next happy birthday to you happy birthday dear jyy birthday to today is Jimmy's birthday Jimmy and his classmates have fun celebrating special days like birthdays Jimmy's birthday is in the month of March March is the month when spring begins Susan's birthday is in July July is a month in which we all celebrate a special holiday Johnny's birthday comes on the last day of the year there is a holiday in the month of December too it's fun to plan ahead and look for special days but how do we know when to expect days like birthdays and holidays to keep a record of days we use a calendar a calendar helps us measure and count days weeks months and years but how long is a day a month or a year to find out we have to measure time this clock measures time in seconds minutes and hours can you think of a way to measure longer periods of time what period of time do we measure by the sun with this clock we can measure days if we count each day and give it a number we can keep a record of time this record of time is what we call a calendar but where did our calendar or record of time come from the idea of keeping a record of time started long ago even before history began long ago early man had a simple way of telling time he watched the setting and Rising [Music] Sun as early man counted Days by the sun he began to keep a record of days this how the first calendar be in order to keep a record of many days a way was needed to measure longer periods of time as he watched the changing phases of the moon early man began to count the number of days in a moon cycle in this way man began to keep a record of these regular changes or cycles of the Moon the Moon cycle or month was a good way to measure longer periods of time then an even longer period of time was discovered far off in ancient Egypt people noticed that the seasons changed regularly by keeping a record of the changing seasons people found a way to measure the period of time that we call a year then the early Egyptians found a way to measure a year accurately they noticed that a shadow cast by the Sun moved in a regular cycle throughout the year by observing one complete cycle of the Shadow the early Egyptians were able to measure a year by the Sun today we know that one complete journey of our Earth around the Sun measures the period of time we call a year each journey of our Earth around the sun takes a little more than 365 days with a small part of one day left over this means that each cycle of 365 Days of our Earth traveling around the Sun measures a year but what do we do with the part of a day left over at the end of each year since we count only 365 days in a year our calendar is short part of one day each year in four years these parts of days add up to one whole day our calendar becomes short one day every four years do you know how we make up for this day once every four years we add a day to the month of February we call years with an extra day leap years because the calendar helps us plan many of the things we do we should know how to use it correctly what do we do when we write a calendar date first we write the month then the number of the day of the month and finally the year but what does this number do the number of the Year helps us count years in this way we can count the number of years from one event to another over long periods of time sometimes a date in the calendar helps to remind us of something we are planning to do this is how the calendar helps Susan remember her appointment with the dentist and this is how Donald uses a calendar to help him remember when to put money in his bank Bank dates in the calendar can be useful in many ways our newspapers have a calendar date on them this date helps us to know when things happen the post office uses a calendar date on our mail this date shows us when a letter was mailed libraries use calendar dates too each time we borrow a book from the library a date in the calendar helps us remember when the book must be returned by using a calendar we can plan ahead for the changing seasons in what ways do you have fun during these [Music] months what happens at this time of year [Music] what do you like to do during these [Music] months do you see how the cycle of the changing months leads to a new [Music] year the changing SC seasons are important to many people such as Farmers Farmers often use a calendar to know when to plant and when to harvest the calendar helps Farmers to plan ahead the calendar helps us plan for holidays too do you know why we celebrate this holiday what happens on this date by using the calendar we can keep track of all the days that are important to [Music] us our calendar is a record of time divided into days weeks months and years it helps us to keep a record of many important events and to plan ahead for the things we do what are some of the ways the calendar helps you plan the things you do [Music]