Guide - Simple Machines and Linkages

There are three classes of levers used in the everyday world. Build a pair of scissors and explore the mechanical advantage of class one levers. Simulate cutting paper by testing how the levers interact.

Please note this resource was tailored for US schools and may require adjustments to suit UK schools.

🇬🇧 Teacher Notes

### Lesson Structure

 When students go through this lesson in each section, the objectives they will learn are:

* **Imagine** – Learn about scissors composed of two simple machines.
* **Build** – Join class one levers to make a pair of scissors.

Teacher Notes

Overview and Objectives

Materials

#### Teachers: Preparing Your Students (15 min)

When students begin the lesson, they start in [Overview and Objectives](#overview-and-objectives), then transition to this [Preparation](#preparation) section. Presented in their view is a vocabulary list of terms and infographics illustrating concepts across STEAM domains throughout this entire lesson.

There is an extra guide for preparing student readiness for their first engagement of new terms and content knowledge. Print or distribute the guide digitally. 

* Read through the vocabulary list. (5 minutes)
* Review the 6 simple machines. Download the optional asset and share to students. (10 minutes)

#### Vocabulary (5 minutes)

This is the list of vocabulary terms used throughout the lesson. They will be in **bold** and listed throughout the different sections.  Students can always revisit the vocabulary definitions with media and questions in the lesson. (5 minutes)

#### Simple Machines and Linkages (10 minutes)

Review the simple machines and linkages. There is an **optional** guide used as a printout or can be shared online to students before they engage this lesson. Each simple machine is designed to make work easier or more efficient and referenced in this lesson. Download the optional guide. (10 min)

Preparation

### Class One Levers and Compound Machines

* **Simple machines** have few, if any, moving parts.
* A **lever** is a moving beam across a **fulcrum**.
    * An object, known as a **load**, is placed on one side of the beam to be moved.
* In **class one levers**, effort is applied to the opposite side of the beam from the **load**.
    * The **fulcrum**, also known as a pivot point, is located between the **load** and the **effort**.
* A pair of scissors is composed of two **simple machines**, making this cutting-edge tool a **compound machine**.
    * The edges of the blades are actually 2 wedges, crossed over at the **fulcrum**.
    *  The blades connected to the handles act as two **class one levers**.

As a hand closes the handles of the scissors, the most **force** is applied when the **load** is closer to the **fulcrum**. This makes clean and straight cuts into the piece of paper.

Imagine

Build handles

Add beams for extending handles

Make a joint for the pivot

NGSS

Florida - NGSSS

Build

References and Extra Resources

STEAM Classroom

United States

Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost.

3-5-ETS1-1

Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.

3-5-ETS1-2

Plan and carry out fair tests in which variables are controlled and failure points are considered to identify aspects of a model or prototype that can be improved.

3-5-ETS1-3

Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.

MS-ETS1-1

Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

MS-ETS1-2

Students develop, test and refine prototypes as part of a cyclical design process.

ISTE Students

1.4.c Innovative Designer

Students communicate complex ideas clearly and effectively by creating or using a variety of digital objects such as visualizations, models or simulations.

Intro: Class One Levers

Overview and Objectives

Lesson Structure

Overview