ESTIMATION:

HOW CLOSE CAN YOU GET?

Knight Foundation Summer Institute

Jeffrey Tecosky-Feldmen, Haverford College

Jennifer Fisher, Bryn Mawr College

Introduction:

We use estimation every day in our lives. People need to be able to guess how far 100 yards is so that they can stop their car before a stop sign. We need to estimate height to see if we can fit though a small place. All of the judgment that we use to maneuver through our lives is a result of estimation.

The teacher could begin this lesson by asking the students how big they think a bowl is. The students could also be asked which of two spaces is bigger by comparing them using materials available in the room. The teacher could also talk about the different kinds of estimation that we use every day. The students could come up with a list of things that they need to know the size of in their lives. ~

In this lesson, Haverford College is used as the "playground," but the lesson can easily be modified to work in any park setting. With a little further imagination and work, the lesson could be done right outside of an urban school or even in the classroom.

Objectives:

  1. To have the students get a feel for sizes, specifically height, volume, area, and weight
  2. To learn to use simple objects as a reference point to figure out the sizes of other objects
  3. To have the students use their imaginations to figure out methods to estimate the size of the required objects
  4. To get the students outside and active and to show them the relevance of math in their everyday lives

Vocabulary:

Estimate

Approximate

Circumference

Volume

Materials:

Procedure:

  1. Give the need supplies to each group
  2. Explain that each group must find the indicated measurement of each object in feet, square feet, cubed feet or pounds, whatever the object calls for
  3. Explain that the students can use the string, their bodies and any other natural material that they find to obtain their results
  4. Have the students compare their results and discuss what methods they used to get their results

Assessments:

The process that the students used to find their estimations is what is important. The teacher could award a prize to the most creative method that one of the groups used.

If there is any way to know the actually measurements of the objects, the teacher could share these results with the students and they could about how close (or far away) they were from the actual results. The teacher could lead a discussion as to why their results might have been so far off.

Extension:

The teacher could ask the students if they felt they had learned how to estimate better because of this activity. A discussion could be lead that would let the students explore the different ways in which estimation is in every part of their lives. Each student could be asked to write a short story in which the main character must estimate something for an important reason. Besides setting up a situation where the students must relate this area of math to their everyday lives, they will have to create an imaginative way to solve the problem using only the material around them.

Cross References:

In the activity, if the students are brought to a park, it is a great opportunity for them to learn about their environment. For example, they might have to estimate the height of a tree and in the process could learn the name of the tree. It will help to bring about a respect for the environment. In addition, in the extension, the idea of writing about the method uses language arts skills.

Provide estimates (in feet, square feet, or cubic feet, as appropriate) for the following measurements. You may use the string that your teacher has given you as well as your body or any other natural objects that you find. Please also write down the process that you used to get each of your answers.

  1. The circumference, area and volume of the duck pond.
  2. The circumference, height and volume of the tallest tree just across from the road from the duck pond.
  3. The volume of the small shack next to the duck pond
  4. The volume and weight (in pounds) of the largest duck you can find.
  5. The weight (in pounds) of the water in the duck pond.