Guide - Simple Machines and Linkages

There are three types of levers used in the everyday world. Try building a set of tweezers, an example of class three levers. Discover how the position of a pivot point on a lever can change the function and purpose of this lever with hands-on prototyping.

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** – Dive deeper into levers by examining types and purposes of class three levers.
* **Build** – Build a prototype of tweezers collecting small objects.

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 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

### Purposes of Class Three Levers

* A **class three lever** has its **fulcrum** on one end of the beam, and the **load** on the opposite end.

  * **Effort** is placed between the **fulcrum** and the **load**.
  * In a **class three lever**, the **effort** arm is always shorter than the **load** arm.
* **Class three levers** do not make work easier, but they make work faster.

  * Examples include tweezers and fishing rods.
  * Tweezers can pull tiny hairs or splinters at a faster rate than if people try to pull them with their fingertips.

While c**lass three levers** don't have a great mechanical advantage compared to class two levers, it multiplies the speed they can perform a task.

Imagine

Connect beams to make tweezers

Add pinchers to the tweezers

Create a resistant middle inside the tweezers

Practice picking up small objects

Change the size of the beams and test for efficiency

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 Three Levers

Overview and Objectives

Lesson Structure

Overview