**Introduction**

The mathematical constant?, sometimes written as Pi, is approximately equal to 3.14159... Each year, Pi Day is celebrated on March 14 by math enthusiasts around the world. You have been selected to explore the meaning of Pi and to celebrate Pi Day through online activities.

**The Task**

To prepare for these explorations, you will need to browse some lessons on circumference and area of circles. Next, you will engage in web-based inquiry to explore the meaning and history of Pi and calculations involving Pi. You will also explore the history of Pi Day and how it is celebrated. You can then celebrate Pi Day by engaging in online activities of your own choosing. Links to resources on Pi and Pi Day are provided. These tasks will require a computer, access to the web, paper and pencil.

**The Process**

**Process Part I: Learning About Pi**

- Read our?Unit on Circumference and Area of Circles.
- Complete the exercises at the end of each lesson in this unit. .
- Try our?Circumference and Area Worksheets.
- Try our new Interactive?Circle Puzzles?with buttons and timers.
- Visit?Pi Day, the official web site for Pi Day.
- Visit?The Exploratorium's Pi Day Celebration.

**Process Part II: Learning About the Meaning and History of Pi**

- What is the relationship between the symbol??and the word Pi?
- The value of Pi comes from what ratio?
- Why is Pi called a mathematical constant?
- Why does Pi continue infinitely?
- Why is Pi an irrational number?
- How many digits of Pi are known?
- Which mathematicians first used the symbol?? Why?

**Process Part III: Learning About Pi Day**

- Why is Pi Day celebrated on March 14?
- For how many years has Pi Day been celebrated?
- March 14 is also whose birthday?
- Who tried to find the first calculation of Pi?

**Process Part IV: Celebrating Pi Day**

Spend a few hours celebrating Pi Day by engaging in online activities. You may choose activities from the suggested sites listed below. Or find your own activities by searching?Google?and?Yahoo!

- The Exploratorium's Pi Day Celebration
- The Joy of Pi
- The Math Forum Pi Day
- On Pi Day, one number 'reeks of mystery'
- Pi Day
- TeachPi.org
- Visualizing Pi

**Resources**

- Unit on?Circumference and Area of Circles.
- Selected?worksheets?and?puzzles?from Math Goodies.
- Selected websites listed in the Process sections above.
- Search engines such as?Google?and?Yahoo!

**Evaluation**

- Note the immediate feedback in the exercises from each lesson above.
- View the solutions to the crossword puzzles above.
- Write about Pi and Pi Day in your math journal.
- Share some of the online Pi Day activities you chose with a classmate or family member.
- Create your own Pi Day activity, such as a song, an image, a poem, or a poster.
- View the Pi Day cartoons and jokes on our?Facebook page.

**Conclusion**

Congratulations! You learned about the meaning and history of Pi. You also learned about Pi Day and celebrated through activities you found on the web.