The Global Grocery List Internet Project

Overview: Students collect prices on 14 specific items from their local grocery stores. The data is entered into a spreadsheet, sorted and averaged. The information is then sent to the Global Grocery List web site and becomes part of a growing table of data. The data is analyzed providing the students an opportunity for solving many problems.

Goals and objectives:

Students will collect data from local grocery stores, enter the data into a spreadsheet, and manipulate spreadsheets (sorting, averaging, graphing, etc.).

 

Prerequisite skills/knowledge:

Skills: Students must have basic computer skills ( using a mouse, using a keyboard, etc.) Levels of understanding: Students must understand the concept of averaging numbers.

Materials/equipment:

Hardware

One Macintosh computer which can be moved into the math classroom
Macintosh Lab with a computer for each student
Internet connection (this could be at the teacher's home)
modem .

Software

Claris Works - Example of Spreadsheet Used [PDF file ]

Printed Materials

Letter to parents with student worksheet attached [PDF file ].

Online Resources

(1.) The Global Grocery List Project can be found at this address:
http://www.landmark-project.com/ggl.html

(2.) Teachers can submit lists at this address:
http://www.landmark-project.com/ggl/submit_web.html

(3.) Currency exchange rates are found here:
http://www.oanda.com/cgi-bin/ncc

Instructional activities/strategies:

Classroom Management:

The teacher introduces the project three weeks before going to the computer lab. Students go to the grocery store and record the prices of the items on the list. Students must also record the price of one gallon of premium unleaded gasoline, the name of the store, and the name of the gasoline station. At the conclusion of two weeks, students begin typing their data into a spreadsheet on a computer located in the mathematics classroom. This data entry occurs during the students' independent practice time in math class each day for several days. With over 100 students, this process takes about 5 days. Students can also enter data before or after school , or during advisory or study hall , if permitted.

 

Questions to investigate:

(1.) Students often do not find the exact item they need at the grocery store. This leads to discussions of converting units, finding unit prices, and using proportions to solve problems.

 

(2.) Students question which brands of food they should look for. Prices vary greatly between national brands and store brands.

 

(3.) Many of the items on the list can be interpreted in a number of ways. The class and the teacher need to decide things like "is it butter or margarine, or does it matter?"

 

(4.) When analyzing the Global Grocery List, students notice significant price differences on products across the country. Questions such as these can be posed: "Why is the price of milk $4.97 in Hawaii and $2.19 in Texas?"

 

(5.) The size of the spreadsheet is very large. Students discover that large amounts of information which cannot be managed by the human mind can be managed with accuracy by a computer. Students can compare prices from the different stores in their area and determine which store offers the best prices.

 

(6.) Some items in the spreadsheet are obviously incorrect. Questions can be raised such as, "Who can enter information into this spreadsheet?" "What should we believe when we access information from the Internet?" "What types of sites are more reliable?" "When doing a research project, which types of sites should be used?" Other topics such as ethics can be discussed.

 

(7.) It is impossible to see all of the spreadsheet on one screen. Graphing can be used to help the students compare data.

 

Sequence of lesson:

On the first day of the project, the teacher distributes the parent letter and the global grocery list worksheet to the students. The teacher and the students discuss the project and go over the grocery list. Students go to the grocery store some time during the next two weeks, taking their grocery list with them. Students record the prices they find at the grocery store and at the gasoline station on their worksheet. After they complete the list, students bring their worksheets to the computer in the classroom and enter their data into a spreadsheet.

 

After all of the students enter their data into the classroom computer, they go to the computer lab. In the lab, students study the spreadsheet they have generated with their data. They average the prices of each item on the list using the functions of the spreadsheet. They sort the data by store. They compare prices by store. They compare the prices of one gallon of premium unleaded gasoline. They create different types of graphs to compare prices of different items (i.e., hamburger prices compared to rice prices).

 

Before students go to the lab, the teacher must download the current Global Grocery List from the Internet into a spreadsheet. The teacher may also download past years' lists. The students spend time analyzing data from the Global Grocery List which is currently on the Internet and data from previous years' lists. Students learn how to manipulate extremely large spreadsheets. Time is also spent creating bar graphs, line graphs, and double bar graphs comparing data. Students discuss the impact of missing data and of data which is clearly incorrect.

Communication: Students share their ideas verbally through class discussion.

Assessment options:

The students will hand in the worksheet of data collected from local grocery stores. This worksheet is graded by the teacher.

Teaching Suggestions/Extensions:

Students can write reports or create multimedia products of their findings. Students can investigate currency exchange rates at this web site: http://www.oanda.com/cgi-bin/ncc

 

Contributor:

Mindy Hensen

Cedar Valley Middle School 

Round Rock ISD