This is an explanation of a math writing project I do with my 7th grade students in which they discover ways of describing everyday objects in mathematical terms.

1. Glenn Kenyon The San Francisco School glenkenyon@yahoo.com where’s the math? describing the math in everyday things

3. The San Francisco School. 50% students of color. 50% from public elementary schools. 40% on scholarships. 48% of my life as an educator Who Am I? about 4,100 days with students or about 25,000 hours Math specialist for 18% of professional life bilingual teacher for 82% 28% in kinder/first, 54% in 4/5 18% in Middle School I’ve worked with a little over 1,800 students and their families

4. Text

5. For you personally, Math is primarily an art, a language, a science, a tool, a way of life, a distant memory, a nightmare, or something else entirely?

6. An exquisite expression of human culture. For me math is primarily:

7. What is a cultural artifact? Culture is how you live your life What are the objects you possess that help “live your life” ? So cultural artifacts are what you use to live and think

8. Make a list of your own personal cultural items that you could potentially describe mathematically. Feel free to take risks (You won’t be obliged to pick an artifact from your list)

9. My cultural artifact: The Necktie

10. Description A necktie is a long piece of fabric, often silk, that is worn around the neck and hangs down along the center of the torso. It is tied in a specific triangular knot around the neck and often is tucked underneath the shirt collar. It is typically worn by men in formal situations, although women can also wear them. Rationale I chose this artifact because it represents a dilemma I face as a Californian and as a teacher. I personally like neckties because they can be fun and colorful in an otherwise boring male wardrobe. At the same time, it can be uncomfortable to wear something close around the neck, especially when buttoning up the dress shirt. As a Californian I have been in very few situations where a tie was mandatory. As a teacher I have always worked at schools where ties are considered SUSPECT. But as a person, I like wearing ties on a regular basis. Hence, I chose the NECKTIE a my cultural artifact.

11. Pick a couple of math topics from each section to describe your artifact

12. the math behind a necktie number proportionality measurement/geometry algebra what fraction of my tie is red? convert this fraction into decimals? what percentage of my tie has numbers? what is the ratio of numbers and letters on my tie? what are the dimensions of my tie in inches and centimeters? how much material was used to make my tie? what is the approximate area of the trapezoid knot? how can i convert my measures from inches to cm?

13. the math behind a necktie Fermi Question On a given work day, about how many ties are worn in California? • California population: about 36 million • Maybe half live in urban settings: 18 million • Maybe half of those are adults: 9 million • About half of the adults are men: 4.5 to 5 million • Ties are worn in certain professions on regular basis, but many jobs don’t require them • I estimate that between 10% and 25% of working men wear ties: 10% of 5 million: 500,000 to 25% of 5 million: 1.25 million • I believe the number of necktie wearers on a given day in California is between 0.5 and 1 million , a very small percentage of the entire California population.

14. http://www.youtube.com/watch?v=Ug75diEyiA0&feature=player_embedded

15. the math behind the hamburger

16. the math behind the hamburger With a partner, generate some questions/answers that lead to a mathematical description of a hamburger. Your task: Use the resources provided and/or other info. You will be sharing your work with the group Think of a FERMI QUESTION for a hamburger

17. the math behind the hamburger

18. the math behind other artifacts: or anything else you have with you Generate a math description of one of these artifacts:

19. looking @ student work

20. workshop evaluation

21. resources

22. Fermi Questions in the middle school ( http://www.nctm.org/eresources/article_summary.asp?URI=MTMS2008-12-280a )

25. http://nutrition.mcdonalds.com/nutritionexchange/nutrition_facts.html

26. http://www.in-n-out.com/pdf/nutrition_2008.pdf