## POP CLOCK

Susan Boone --sboone@cs.rice.edu
Subjects: 8-12 Mathematics
Topic: Data Collection, Problem Solving, Research Skills, and Interpolation of Data
June 27, 1995

Purpose: Students will review the Census Bureau's Homepage on the Internet and gather data regarding trends in population. They will study this data and make predictions on future populations and compare their results with the information available on the Internet.

Materials: Internet access, ruler, graph paper (optional)

Prior knowledge: This lesson can be modified to address various levels of mathematics. Depending upon your students abilities, you can change the type of questions asked. I am focusing on entry level Algebra I students.

Description: The Internet site used for this lesson provides a great deal of data dealing with social issues. This lesson lends itself particularly well to social studies. Mathematically, students will be asked to collect data over a given period of time and record this data in a meaningful way. I recommend making a large chart on a bulletin board for groups to post their data. This Internet site provides up to the second population counts. Students should be placed in groups of two or three and instructed to 'gather" the data on the population count. They should record the time and the number. Post this data on a designated spot in the classroom. This count should be collected at the beginning of their time on the computer, and again at the end of the period. ( More data can be collected if their is time). Research techniques will be required to answer relevant questions regarding this particular Internet site.

Time: This lesson could be done if there is only one available computer to access the Internet. Groups of two students could work on this assignment independent of other work. This lesson could easily be modified to accommodate various ongoing group activities.

Procedure: Divide the students into groups of two or three. Over an assigned period, have students collect data from the Census Bureau Homepage regarding current population counts of the nation. Students will record this data and at the end of the lesson, the class will decide on a reasonable functional representation of the data. Discussions could follow as to how this interpolation was made. Compare the class results with the available predictions found on the Internet site. Many social issues are addressed regarding the life expectancy of males and females, aid for children, and statistics on unwed mothers. Students should answer the question portion of this lesson plan. Students can use the Census Bureau Homepage to research the data needed to determine the answers for the following questions. Students should include the location (URL) for the location the correct data for each question was found. this information can be found in the location box from the Inter browser screen.

Once the assignment is completed by all groups (this could take several days), study the population data recorded on the classroom chart. Discuss how these populations were determined. Ask students to predict an appropriate functional representation of the data. Is the function linear? (it will appear this way because of the relatively short amount of time the data was collected). Could a different function represent the data better? (exponential). Using the data, predict the population for next week, next year, and in ten years. Compare these results with those found on the Census Bureau Homepage.

Questions: (Be sure to include the URL of the web site that you found the answer to these questions.)

1. Select the Population Clock from the Census Bureau Homepage. Record the population and time for the nation. Is this the "actual" count? Explain how this number was determined.  (Note that this assignment is designed to be a group project.  If you are working on this individually, collect at least 20 population counts over the span of the project.  Each count should be dated and recorded on a data sheet.  Plot these data points on a graph.)

2. What is Houston's (or any city of your choice) most recent documented population? What is the URL (location) you were in when you determined this answer?

3. What is the name of the director of the Census Bureau?

4. What is the fastest growing occupation? What could contribute to the increase in this profession? What is the URL (location) you were in when you determined this answer? The Bureau of Labor and Statistics is a great place to "search" for Occupational Growth statistics. You will find Occupations with the largest job growth from 1994-2205.

5. What percent of Consumer Expenditures is for food? for transportation? URL(location)?hint: There is a search feature within the Census Bureau's web site. The Bureau of Labor and Statistics also has a search feature. There are even Consumer Expenditure Surveys found within this site.

6. What is the ratio, (rounded to the nearest whole number) of female to male custodial parents (as of 1992)? URL (location) used? hint: this information deals with Child Support

7. What percent of mothers receiving Aid to Families with Dependent Children was never married? URL (location) used?hint: try searching for AFDC (Aid to Families with Dependent Children)

8. Return to the U.S. Census Bureau homepage. What is the population of the nation now? Record the population and the time. If you are doing this project individually, you should collect at least ten (10) different population counts. Be sure to record the day and the time you collected them. If you would like to put this data in chart form, the entire class' data can be used to make a graph.

If you are doing this as a group assignment in class, give your answers to the teacher and record your population data (answer to number 1 andl 8) on the posted chart. If you are doing this as an individual assignment, you should compare the answers to number 1 and number 8.

Extension: Research the amount of Aid to Families with Dependent Children given in the Houston (or nearest large city). How does this number compare with the National average? The AFDC site lists information on various parts of the country. Your data can be from the South/Central region, or you could discuss metropolitan areas in general. Report why this trend is present. This information may be difficult to find on the Internet. You may need to contact the local government agencies by telephone or letter.

Gender Issues: Write your opinion on custodial "mothers vs. fathers". Why do you think a discrepancy in funding exists?