Machines and People

Grade Level

3 - 5

Purpose

Students define the word "machine," explain how machines are used in agriculture to produce food and fiber, and compare and contrast a variety of machines. Grades 3-5

Estimated Time

Four 30-minute sessions

Materials Needed

Activity 1: Brainstorming the Definition of a Machine

Markers, 1 set per group
12"x18" white construction paper, 1 piece per group

Activity 2: Discovering a Machine

Big Book of Big Tractors
The Tractor picture
People and Machines activity sheet, 1 copy per student pair
Pictures of a variety of machines, 1 per student pair

Activity 3: Similarities and Differences of Machines

Pictures of a variety of machines, 2 per student pair
Venn Diagram activity sheet, 1 copy per student pair

Activity 4: Machines at My House

Machines at My House activity sheets, 1 copy per student

Vocabulary

machine: an apparatus using or applying mechanical power and having several parts, each with a definite function and together performing a particular task; a device used to help make work easier

Background Agricultural Connections

This lesson is part of a series called, Simple and Complex Machines Used in Agriculture. These lessons introduce students to the simple and complex machines used in their daily lives and in food and fiber production. Through a variety of hands-on activities, students create models of the six types of simple machines and discover the concepts of force and friction. The essential role of complex machines in people's daily lives and in agriculture is interwoven through a number of class and homework activities that incorporate cooperative learning, writing, mathematics, art, and drama. Together these activities are designed to stimulate creative thinking and motivate learning. Other related lessons include:

A machine is a device used to make work easier. People appreciate machines because they save time and human energy. Machines are a basic part of our heritage. The human's innate genius for invention and tinkering has resulted in the creation of many machines. Thus, machines have turned people's dreams into reality. Almost everything people do depends, in some way, on machines—simple or complex.

The word "machine" itself is derived from the Greek mechane and the Latin machina. Both loosely translated mean "an ingenious device or invention."

There are six simple machines from which complex machines are made: lever, inclined plane, wedge, screw, pulley, and wheel and axle.

Engage

Show students a very large, heavy object. (Use a picture or something around the school or playground). Ask them if they could lift the object by themselves.
Once they determine they couldn't lift it with their own strength ask them if they could with the help of a tool or machine. Could they lift it with a tractor? Could they use a lever?
Ask your students if they can name examples of tools used on a farm or in everyday life.
Ask if they can name some machines used on a farm or in everyday life. In this lesson students will be learning how machines help people perform work.

Explore and Explain

Activity 1: Brainstorming the Definition of a Machine

Review with your students your rules for brainstorming and cooperative group activities.
Place your students in groups of three or four students. Give each group a set or markers and one piece of white 12"x18" construction paper. Instruct the "scribe" or "recorder" of each cooperative group to write one of the following questions on each side of the white paper. Read the questions aloud as you write them on the board:
- What is a machine?
- Why do people use machines?
Explain to the students that they will do two brainstorms. They will have three to five minutes to brainstorm and write their answers for the first question. At the signal they must stop, turn their paper over, and brainstorm answers to the second question. If necessary, adjust the time for each brainstorm. It is important to provide enough time to write down major ideas, but not quite enough time to write every detail.
Have the groups complete their brainstorms.
Allow three to five minutes for each group to review and determine two of their "best" or "most unique" answers from each brainstorming list. Have each group write their choices in complete sentences on four separate sentence strips.
Have each group post their answers under the appropriate brainstorm question that you have written on the board. Encourage a classroom discussion about the sentences.
Create a class definition for the word "machine."

Activity 2: Discovering a Machine

Read the book, Big Book of Big Tractors by Lisa Jane Gillespie and Mike Byrne. This book describes and illustrates many machines used in agriculture. Help students understand that various machines make the production of our food more efficient. Our food and some of the fiber used to make our clothes and other necessities come from farms. Machines used on farms make it possible for farms to produce enough food for our population. As you read the book, ask the students, "If a farmer did not have this machine, how would he/she [insert task name here]" For example, without a Seed Drill, how would a farmer plant hundreds or thousands of acres of corn or wheat? In most cases the labor would have to be performed by hand. Help students see that it would not be possible for farmers to produce enough food for our population without machines.
Project The Tractor picture on a large screen and lead the class in a discussion that previews the questions on the People and Machines activity sheet. Discuss that scientists call machines either "simple" or "complex." The tractor is a complex machine made of simple machines such as wheels, axles, and levers.
Group students into pairs. Give each pair of students a pencil, a picture of a machine, and one copy of the People and Machines activity sheet. Instruct students to use their pictures to answer the questions on the activity sheet. You may choose to give teams pictures of soil preparation equipment, planters, cultivators, harvesters, etc. Allow sufficient time to complete the activity. Have each pair share their answers with the class. Discuss the variety of equipment farmers use.

Activity 3: Similarities and Differences of Machines

For this activity sheet, each pair of students will need a pencil, two pictures of machines, and a Venn Diagram activity sheet. If you have not previously performed a Venn diagram activity with your students, take time to do one as a whole class before proceeding.
Instruct the students to write the name of one machine on the line in one of the circles and the name of the other machine on the line in the other circle. In each circle, they should list the characteristics that are unique to each particular machine. Where the circles intersect, the students should list ways in which the machines are similar.
Have students volunteer to share their results, and/or create a bulletin board to display the Venn diagrams.

Activity 4: Machines at My House

Distribute one or both of the Machines at My House activity sheets and explain the homework assignment(s) to your students. Have the students complete the assignment(s) at home.
After collecting the homework, discuss what it would be like if certain machines were not available to assist people in the kitchen.

Variations

Using a picture of a machine and a variety of materials, have students invent an improved machine.
Do the Venn diagram as a whole class activity.
Have students write a description of how to build or plant something. Their explanations must include a description of the machines used in the process.

Elaborate

Make Peanut Butter:

For each group of 3-4 students:
- Two cups roasted peanuts in shells
- Nutcracker
- Plastic knife
- Crackers
1. Have one-half of the students in each group shell peanuts by hand while the others use the nutcracker. When partly finished, have the students trade jobs.
2. With your assistance, have each group take turns putting their whole peanuts in a blender and blend until smooth. Discuss how the peanuts could be ground if a blender were not available.
3. When the peanut butter is made, use the knife to spread it on crackers.
4. As the students enjoy their snack, have them discuss the following:
  - What machines were used to make the peanut butter?
  - Which machines made the work faster or easier?
  - Would the final peanut butter product have a different appearance if different machines were used?
  - As a class, read the book, From Peanuts to Peanut Butter.
*Safety Note: Be advised of any food allergies before making a decision to conduct this activity with students.
Play the My American Farm interactive game Equipment Engineer.
Read Issue 5 of Ag Today titled Agriculture in Society. This reader can be accessed digitally. Students will learn the term sustainability and what that means to farmers who need to produce 60% more food with the same amount of land in order to feed a growing world population. Learn what byproducts are and how they are used, how food packaging has decreased waste, and how farmers use technology such as various tools, robots, and hand-held devices to improve their efficiency.
Draw Around: In this activity, each student will need a pencil, a photograph of a machine, and a piece of drawing paper. Place students into groups of five or six. Allow students two or three minutes to draw a part of their photograph before passing it along and receiving another photograph passed to them by a fellow student. Each student will then draw a part from the new photograph. This should continue until each student has incorporated a part of each photograph into his or her own drawing. The result will be a drawing of a new machine. The students may give their new invention a name, describe what it might be used for, color it, add some background, and then display it.
Yes or No: This game is similar to 20 Questions. Give one pair of students a photograph of a common machine. They must not let anyone else see it. Have the rest of the class try to guess what the machine is by asking questions. The questions must be answerable with a simple yes or no. If the class cannot guess the machine's name in twenty questions, the team holding the photograph is the winner. Bicycles, hoes, shovels, screwdrivers, lawnmowers, and stairs are good machines to use in this activity.

Evaluate

After conducting these activities, review and summarize the following key concepts:

Simple and complex tools make work easier and more efficient.
Food comes from farms. Farms require a lot of physical labor to plow fields, plant and harvest crops, and raise animals. Machines replace the work of many people and make work more enjoyable.
If work on the farm is easier and more efficient, it makes it possible for the farmer to produce more plants and livestock that become your food and or more fiber or trees that become your clothing and shelter.

Acknowledgements

This lesson was funded in 1996 by the California Beef Council and the California Farm Bureau Federation. To meet the needs of California educators, Simple and Complex Machines Used in Agriculture was revised to support the Curriculum Content Standards for California Public Schools and updated to include recent agricultural innovations. Funding from the Wells Fargo Foundation made this revision possible.

Illustrators: Karin Bakotich, Pat Houk, Sherri Hughes, Regina Johnson
Layout and Design: Nina Danner