## Background Sadako was a young Japanese girl who suffered from leukemia because of the atomic bomb that was dropped over Hiroshima when she was two years old. "Tsuru" the crane, is an ancient Japanese symbol of long-life, hope, good luck and happiness. She believed that if she folded 1000 paper cranes her wish to get well and live and a long life would come true. Sadako said of the cranes, "I will write peace on your wings and you will fly all over the world." However, Sadako was only able to fold 644 paper cranes before she died. You can find out more about Sadako by reading the book by Eleanor Coerr, Sadako and the Thousand Cranes. Sadako became very weak towards the end, but she never gave up folding paper cranes. In the following activity, you will try to determine approximately how long it took Sadako to fold her paper cranes.

### Directions:

1. Practice folding the paper crane until you think you have mastered all the folds. Click on the thumbnail to see the larger version of the steps for folding the crane.
2. Once you have mastered the paper crane, set the stopwatch to time how long it takes you to fold the crane. Repeat this step at least three times and find your average time.

## Timer

3. Use the calculator to determine how long it would take you to fold 644 cranes, in minutes, hours, and days.
4. Based your data, how long would it take to fold 1000 cranes?
5. How many more cranes did Sadako need to fold in order to meet her goal of 1000 cranes?
6. Based on your data, estimate the length of time, in hours, needed to complete Sadako's goal of 1000 cranes.
7. Submit your name, school, age, and time so that we can post your results to compare with others.