1. Introduce this lesson by asking student what day it is: when they answer, ask them if they are sure that is the case. Suggest that it might, perhaps, be 11 days later. At least, that is what happened once in our history!
2. Explain the terms Julian and Gregorian with respect to calendars. Then, divide the class into six groups, and using the web sites listed below, assign each group the following task:
Group 1: How were the months of the year named? By whom?
Group 2: How were the days of the week named? By whom?
Group 3. What is the history of the Julian calendar?
Group 4: What is the history of the Gregorian calendar?
Group 5: What are the strengths and weakness of each calendar?
Group 6: What is at least one criticism of the Gregorian calendar?
3. When the research is completed, ask each group to prepare a poster that will demonstrate its findings, and share it with the whole class. Mount the posters around the classroom.
4. Conclude the lesson with a discussion of what might be missed if 11 days were taken out of our calendar. Use some of the following examples and discussion starters:
- What if we went from December 17th to December 28th?
- What if we went from July 1st to July 12th?
- What if we went from February 3rd to February 14th?
The Julian Calendar
The Gregorian Calendar
The Curious History of the Gregorian Calendar
The British Calendar Act of 1751
Naming the Days of the Week
How Britain Got the Calendar Wrong
This lesson was developed by Averil McClelland, Kent State University.