Institute for Dynamic Educational Advancement
Web Exhibits: Calendars Through the Ages: Announcing the Sky
Well-organized website depicts the "Fascinating history of the human endeavor to organize our lives in accordance with the sun and stars." Gives an overview and specifics of the basis of calendars through the ages.
Scholastic
Scholastic Internet Field Trip: Calendars & Time Measure
Study the math and history involved in the development of the 12 month calendar. There are lots of links to informative time and calendar websites to assist you.
Ohio State University
Ohio State University: A Brief Introduction to the Islamic (Hijri) Calendar
Provides background information about the Islamic Calendar, also called the Hijri. Explains the differences between the Gregorian calendar and the Islamic Calendar; lists important holidays and the months of the Islamic year. Provides...
Khan Academy
Khan Academy: Common Questions About Dates
Our calendar is called the Gregorian calendar and was instituted by Pope Gregory XIII in 1582. There are many other calendars. Learn about these calendars and the meanings of B.C.E and C.E.
Other
The Maya Calendar: A Converter
Gives the Mayan days and months. In addition, a Java Applet is included which will convert any date (Gregorian calendar) to its corresponding Mayan date.
Other
Timekeepers.org: Calendar History
Scroll down this page to see the various topics addressed on this website. Learn a "brief history of the Western Calendar" as well as information about the ancient calendars of the world, including the Sumerian, Egyptian, and Greek...
Institute for Dynamic Educational Advancement
Web Exhibit: The Islamic Calendar
This website gives very detailed information about all aspects of the Islamic calendar.
Institute for Dynamic Educational Advancement
Web Exhibit: The Christian (Julian) Calendar
This website gives very detailed information about all aspects of the Christian (Julian) calendar.
Institute for Dynamic Educational Advancement
Web Exhibit: The Indian Calendar
This website gives very detailed information about all aspects of the Indian calendar.
Wolfram Research
Wolfram Science World: Islamic Calendar
A very brief description of the Islamic calendar, which "has its starting point at the date of the flight of Mohammed from Mecca to Medina." Describes the format of the Islamic year in comparison to the Gregorian calendar.
NumberNut
Number Nut: Calendar Origins
History and mathematics merge in this lesson that explores the origin of the calendar. Learn how it all got started in this detailed lesson that includes a simple months of the year game and a more challenging time conversion game. Both...
ClassFlow
Class Flow: Calendar
[Free Registration/Login Required] The history of our calendar is presented through the passage of time with complete cycles of seasons in ancient history providing a starting place. Complete cycles of seasons are discussed and the...
Rice University
Galileo Project: Christopher Clavius
This site from The Galileo Project of the Rice University provides a biography of Clavius including an excerpt from his writings. A picture is provided in this article along with links to additional information.
Other
Western Washington University: Leap Year
It takes the entire page but by the end of it, you will understand the whys and whens of Leap Year Day.
Institute for Dynamic Educational Advancement
Our Year
The concept of a year in time and the various kinds of year used in human timekeeping are discussed.
Other
Torah.org: Seven Questions About Rosh Hashanah
A question-and-answer fact sheet about Rosh Hashanah that addresses when, why, and how the festival is observed. Tells why the shofar is sounded on this day and why apples dipped in honey are eaten. Also explains the differences between...
Library of Congress
Loc: George Washington Was Born Feb. 22
An interesting background on the origin of Presidents' Day, and the actual date of George Washington's birth. Includes a portrait of Washington, as well as an historical letter from Tobias Lear, recounting the Julian and Gregorian...
Other
Cyber Kids: Happy Hanukkah
Brief description of why Hanukkah falls on different days every year. Illustrates the differences between the Gregorian and Jewish calendars.
Curated OER
Cyber Kids: Happy Hanukkah
Brief description of why Hanukkah falls on different days every year. Illustrates the differences between the Gregorian and Jewish calendars.
Wolfram Research
Wolfram Science World: Bede, the Venerable
Encyclopedia entry for the English scholar who wrote a history of the early centuries of Anglo-Saxon England and an encyclopedia which consisted largely of excerpts from Pliny the Elder.