GUESSTIMATE
Grades 4-6

In this lesson students will learn to estimate large quantities of data. They will first estimate the amount of beans in a tub, then verify their estimates by using various methods of calculation. In "Eddie Files," Miss Tolliver introduces ancient Egyptian methods of recording this information.
Students will then use one of the methods they have learned or viewed on the video to find a fairly correct amount for a large population to be counted such as cars per household, children per family, usage of certain grocery items per family, etc.

Eddie Files #102C Estimation: Going to the Dogs

Students will:

• estimate the amount of beans in the large bin.
• verify their estimate by using an appropriate method to calculate a total amount.
• solve a large scale problem posed by the teacher using one of the methods they have learned while watching the video and doing the lesson in class.

• scales
• weights
• small rectangular containers - one per group of 3-4 students such as small boxes or plastic containers
• two larger, identical rectangular bins - one filled with beans, the other empty
• 25 lbs. of beans (less beans can be used, however a greater number of beans is desirable to achieve the same effect)
• calculators
• paper
• pencils
• math journals - optional
• hieroglyphs as per Miss Toliver's lesson - optional (see attachment)
• poster displaying the key for the hieroglyphs - optional

Pose the following question to students: How do we know how many insects a certain number of songbirds can eat in one day? or How do we know how many pounds of oranges are produced each year? Have students write down how they think such problems are figured out.

Arrange students into groups of 3 or 4. Explain to the class that the students in Miss Toliver's class are going to have to figure out how many things there are in a large amount. Explain to the class that they will be doing a similar activity. Remind the children to watch for a few pointers on how they can figure out their problem that you will pose to the class.

In Estimation: Going to the Dogs Miss Tolliver, dressed as an Eygptian, challenges students to learn many ways to estimate and record large quantites of data, including the ancient method of using hieroglyphs. BEGIN the video where Miss Toliver's students are using their math journals to decipher the hieroglyphs she has written on the board.
PAUSE after Miss Toliver has posed the problem of how the children can use their small bins and the large empty bin to help them verify their estimates. Pose this question to the students and elicit responses. RESUME the video until the students in Miss Toliver's class have successfully completed the task and Miss Toliver states, "Your strategy worked."
STOP the video and have students follow part one of the Post Viewing Activity. You will return to the video after the activity is completed.
After Miss Toliver states, "Your strategy worked." and the video has been stopped, show students the bin of beans. Explain that you have a similar problem for each group to work out. How many beans are in the bin? Have students write down an estimate first and share this estimate with the class.
Distribute one smaller container to each group and have students use any method they can think of in their attempt to come up with the number of beans. It would be helpful for the teacher to know approximately how many beans there really are. Once the students decide they have found a way to figure the amount of beans, the real amount of beans may be revealed or the students may have to solve a hieroglyphic puzzle as the students in Miss Toliver's class did.
Follow-up this activity by demonstrating how to use scales to figure out the amount of beans.

Upon completion of the first post viewing activity, RESUME playing the video. After the rest of the Eddie Files #102 has been viewed, discuss with the class how they think the people in the video can make such statements as to how many ladybugs are in each container or how many insects bats can eat.

After the students have watched the second segment of the Eddie Files #102, discuss with the class how researchers might use quantitative data. It is important, for instance, to know how many patients a doctor or a dentist can see during his or her working day. It is also important to know how much food cattle or horses will need each day.
Assign to each student or group of students a problem similar to the one Miss Toliver poses to her students. Have the children work on this assignment for a longer period of time such as a weekend or a week.

This lesson lends itself to further investigations on predicting supply and demand within a community and even the country. In addition, it can lead to discussions about sampling methods in order to learn more about supply and demand.
The class could take a field trip to a factory or a farm. Have students interview the manager in order to learn how the managers of such businesses have to estimate the supply and demand in order to run a well managed business.
Invite a community member who large quantity estimation to the class and have the students interview that person.
Interview the food buyer and menu planner for the school cafeteria. How are food quantities estimated for each school lunch?

If none of the students have used the scales and weights, ask the class how these devices could have been used to figure the amount of beans. If students have a hard time finding a solution to this problem, you may want to model massing a smaller, easier to count amount of beans like a small container full of beans.
Have students count how many beans there are in the small container. Then, students could mass the weight of the beans in the large bin. Divide this mass by the mass of the small container. This will result in the amount of small containers that would fit into the large bin.
Multiply the number of beans in one container by the amount of small containers that could fit into the large bin.

Master Teacher: Gerlinde Wirzfeld-Olvera