# Overview

**Introduction: **Students will extend their knowledge of simple machines to include the lever. Through a hands-on experiment and record sheet, students will demonstrate their understanding of the concept.

**Curriculum Subject and Topic:** Science—Simple Machines

**Estimated Duration:** 30 minutes

**Grade Level:** 3

**Curriculum Goals:** Ohio Academic Content Standards

- Describe the forces that directly affect objects and motion
- Describe and object’s position by locating it relative to another object or the background
- Predict the changes when an object experiences a force (e.g., a push or pull,

weight, friction) - Describe how technology can extend human abilities
- Use a simple design process to solve a problem

**Lesson Objectives:** Students will

- be able to name different types of machines and how they work.
- be able to identify the six basic simple machines.
- be able to label the parts of a lever.
- explain how a lever operates.

**Materials:**

- Computer with Internet access
- Large monitor or projector
- Lever and fulcrum Web site
- Seesaw worksheet
- Cardboard paper towel or toilet paper tubes
- Rulers
- Weights
- Paper for student Unit Journals
- Optional: table, broomstick, sturdy chair, adult volunteer

# Accommodations for Special Learners

- Make sure you pair students together appropriately. Students with physical disabilities should be partnered with able students for the seesaw experiment. The same is true for students with reading disabilities.

# Setting the Stage

- Log onto the Internet and navigate to this example of a lever and fulcrum. Make sure students can see the image.
- Prepare seesaws for each pair of students by cutting in half lengthwise a cardboard paper towel or toilet paper tube. Have a rule available for each student, as well.
- Gather weights for each pair of students. Each pair will need three weights of exactly the same weight.
- Prepare copies of the seesaw worksheet for each student.
- Students will need to have a page ready for their Unit Journals to discuss their learning during the lesson.

# Lesson Activities

**Actvity 1**

- Before starting on the lesson activities, revisit the lever video from the Intro lesson if students need a reminder of the concept. Introduce the idea of levers to students with by discussing that students should be really familiar with one type of lever: the seesaw.
- Ask students how a seesaw works. Tell students that a seesaw includes both a lever and a fulcrum that creates a turning point for the lever to go up and down. All that is needed is weight (load) and force to use the lever as a simple machine.
- Show students the lever and fulcrum example found on the link to the left. Point out the lever, the fulcrum, the weight (load) and the force. Remind students that the force can be a push or a pull, depending on where the lever is at any point in time.

**Actvity 2**

- Once students have the basics, pair them together to complete the seesaw experiment and seesaw worksheet.
- Have each student place their paper tubes flat-side down.
- Then have students balance the ruler on the tube.
- First, guide students to put a weight on one end only.
- Next, show students how to balance one weight on each end of the ruler.
- Finally, tell students to try placing two weights on one end and one weight on the other end.
- Once students have completed all three steps, encourage them to repeat the experiment, stopping to draw what they are seeing in the boxes on their worksheets.
- Allow students 10 minutes to complete this activity.

# Wrap Up

Discuss the seesaw experiment with students. Ask students to tell you if they guessed (hypothesized) what would happen before actually completing each part of the experiment. Then have students share their drawings with you. Make any corrections and demonstrate the correct positioning and labeling using one set of seesaw materials.

Complete the lesson by giving students time to write some observations from today's lesson in their Unit Journals. Have students record in their Unit Journals some uses of a lever and how it makes work easier.

# Supplemental Activities: Extension and Remediation

**An "Uplifting" Experience: **To extend the lesson and show how powerful a lever can be in helping us lift heavy objects, show students how you can lift another adult with the lever. Have your principal, another teacher, or a parent volunteer come into the classroom. Ask the adult volunteer to lay on a long table. Set a large, stable chair with its back close to one end of the table. Using the stick of a broom, lift the adult by placing one end of the stick under the table and using the chair as a fulcrum.

# Assessment and Evaluation

- Unit Journal Entry: Evaluate the students’ observations on levers recorded during the wrap-up activity.
- Seesaw worksheet: Review student drawings, noting any errors and provided appropriate feedback.

[Return to Ed Tech 506] [Intro] [Lesson 1] [Lesson 2] [Lesson 3] [Lesson 4] [Lesson 6] [Lesson 7] [Closure]