### Kevin HollandSanta Rosa District Schools

#### Description

This is an estimation project designed to allow students to find the length of their strides. Using this knowledge, students measure the length of a hallway or find out how many people can fit in the school stadium or gym!

#### Objectives

Uses estimation strategies in complex situations to predict results and to check the reasonableness of results.

Selects and uses direct (measured) or indirect (not measured) methods of measurement as appropriate.

Solves real-world and mathematical problems involving estimates of measurements including length, time, weight/mass, temperature, money, perimeter, area, volume, and estimates the effects of measurement errors on calculations.

#### Materials

-Copy of student worksheets
-Tape measure (25 ft is preferred)
-Class set of calculators

#### Preparations

1. Obtain a 25-foot tape measure and a 100-foot tape measure, if possible.
2. Measure a 100-foot section on a sidewalk, hallway, or paved road. Use the masking tape to mark the beginning and the end. The longer the length of the masking tape, the more students can spread out along the line.
3. Secure permission, if needed, to use the stadium or gym.
4. Copy worksheets for all students.
5. Obtain several calculators to be shared by students.

#### Procedures

1. Hook your students with the question of "How many people can sit in our stadium or gym? How long is the hallway outside our door?" Accept all answers then say: Today, we are going to use a neat estimation technique to find out.

2. Have students go to a 100 foot section of the sidewalk and begin following the directions on the worksheet. (See Associated File) Students need to take pencils, paper, and calculators.

3. They are to walk the length three times. Each time they count the number of steps they take to walk the length and record that number. It is important to emphasize to the students that they need to take regular normal steps.

4. Have students average the three numbers and write down the averages. Divide 100 by the average. This gives them their stride length in feet per step. This number should be between 1 and 3. Check students’ papers to make sure that they divided correctly. A common mistake is to divide their averages by 100.

5. Now that they know their stride lengths, there are many different things that you can measure using this estimate. To calculate the length of an object, multiply the number of steps times the stride length.

6. I like to use this strategy to estimate how many people can sit in the gym or football stadium. Take a tape measure with you.
A. First, have students count the number of steps long a bleacher is.
B. Multiply the number of steps times their stride length. This is the estimated length of the bleacher.
C. Count the number of bleachers on the side.
D. Multiply the number of bleachers times the length of the bleacher. This gives the total estimated length of bleachers on that side.
E. Have the class determine how many students can sit in a 10-foot section of bleachers. This will usually be 7-9 people.
F. Divide the total length of bleachers by 10. This number gives us the number of 10-foot sections on that side of the gym/stadium.
G. Multiply the number of people by the number of 10-foot sections and you have the estimated number of people that can sit on that side.
H. If the opposite side is the same, multiply the number of people by two. If the opposite side is of different dimensions, repeat the process.

7. Another activity that I like to do is estimate the length of a hallway. Usually, before class, I will measure the length of the hallway with a tape measure. I like to use the longest hallway in the school for fun.
A. Have students step off the hallway, counting the number of their steps.
B. Multiply the number of steps by their stride length. This gives us the estimated length of the hallway. Allow students to measure using a tape measure or give them the correct length in feet and let them compare the two mesurements.

8. Summarize the lesson by discussing how this technique is a great estimation strategy. Discuss how land surveyors can estimate the length of parcels of land by stepping off the distance. They don’t have to use a tape measure!

9. Students write a summary paragraph recapping what they did and how this indirect measurement technique can be used in real-world measurement problems.

#### Assessments

Student worksheets should be formatively assessed by the teacher. Students who need feedback should receive it. Please remember that we want students to use estimation strategies. Some answers will not be very close to the actual answer. Worksheets and paragraphs may be assessed by the rubric that is in the attached file.

#### Extensions

This lesson can be extended by creating new problems for students to work using their stride lengths. For example, have the students calculate the perimeter of the school cafeteria, the perimeter of a school building or the area of the room.