The directions are published in the page source document so you can customize colors. This sample article from World Book's online encyclopedia is a good starting point for elementary students. Colorful pictures complement the short, but informative, pages about ancient calendars. There is also information about calendars that are in use today. An Introduction to Calendars An Introduction to Calendars furnishes in-depth knowledge about calendar structures, religion, mythology, and history.
Resources are well-documented with footnotes and links to other pages.
This would be a good starting point for middle and high school students who are working on research projects. You will find the answers to these questions and more along with interactive conversion forms that allow you to convert dates among various calendar systems. There is also a wealth of information about the Julian, Gregorian, Mayan, and lunar calendars. There is also an array of calendar conversion software programs. A quick stop at this site will yield factoids and a picture of each of the early clocks mentioned.