This page provides some Web resources about the measurement of time.
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A Walk Through Time

A series of short essays on the history of timekeeping, from the National Institute of Standards and Technology (NIST) in the U.S. NIST keeps one of the world's main atomic clocks.

Calendar for year

This page generates a one-page printable calendar for this year or next, with the public holidays for your country highlighted on the calendar and listed below it. Several options allow you to customize the calendar’s appearance.

Clock: A History

A series of short illustrated essays on timekeeping through history, including the modern atomic clock.

Clock/Calendar Worksheets and Lesson Plans

EdHelper has a variety of printables and plans for time and calendar skill-building.

Doomsday Clock

The Bulletin of the Atomic Scientists has maintained this famous clock face in its journal since 1947. At the start of this millennium, it indicated "nine minutes to midnight".

Earth Calendar

The national holidays of almost all the world’s countries, and all major religions, are indexed for easy retrieval and viewing.

Encyclopedia of Days

Another indexed compendium of world holidays and special days, some with a sentence or two of explanation.

Frequently Asked Questions about Calendars

Klaus Tøndering of Denmark has assembled a vast FAQ about our calendar – its origins, history, calculation, conventions, and comparisons to other calendars.

Multi Cultural Calendar

KIDLINK has assembled this calendar from students’ contributions all over the world. The children explain the national holidays of about 70 countries, plus a number of religious holidays.

Official Time

This page displays the official time in UTC and in the Western Hemisphere time zones, directly from the atomic clock at the U.S. Naval Observatory in Washington, DC. Through a fast modem in the U.S. and Canada, your displayed "browser time" is within a second or two of atomic clock time.

On this day in…

A selection of anniversary sites, by curriculum topic.

• American History from the Library of Congress, U.S. events with links to historic photos.
  Also from History Channel, with sub-topics like Old West History, Tech History, Vietnam War History.
• Canadian History Extensive list of events in Canada or by Canadians.
• Literature "Ephemerids" in the left column list literary events for this date.
• Mathematics Mathematicians who were born or died on this day, each linked to his or her short biography.
• Science Notable births, deaths, and events (discoveries, patents, debates etc.) in science.
• World History

Teaching with the Calendar

This utility from the portal site TeachCanada.ca displays a few key events or anniversaries in the coming month, each linked to some resource pages that are suitable for student research about the event. The Javascript utility that drives it may be lifted from this portal and placed in your own school or district Website.

Time and Date Worldwide

TimeAndDate.com shows the time in every time zone, and also when your online chat/conference with groups around the world is best scheduled.

Note: For other theme pages in Information Technology, click the "previous screen" button below. Or, click here if you wish to return directly to the CLN menu which will give you access to educational resources in all of our subjects.