Lesson 2: Classes of Levers, Analyzing how a catapult works....

Title: Classes of Levers, Analyzing how a catapult works....

Author: Andrew Stillman

Week: 3

Unit/Lesson Plan #: 6

Unit theme: Materials, Tools, and Machines

Textbook references: FOSS, Levers and Pulleys Module worksheets

Learning objectives:

Students can identify the three major classes of levers in everyday tools and objects.

Students can identify the class of lever being used in their catapult.

Key Questions, Concepts, or Themes:

A lever uses a rigid object and a fulcrum to change the amount of effort required to move a load.

There are three major classes of levers, class 1, class 2, and class 3.

• Class 1: Fulcrum is between the effort and the load. When the effort is further from the fulcrum than the load, it gives mechanical advantage. (Class 1 levers can be reversed, giving DISadvantage, as in a catapult.)
• Class 2: The load is in between the fulcrum and the effort.
• Class 3: The effort is in between the fulcrum and the load.

Stage 1:

Demonstration: Using a 10 foot 2' x 6' and a small block of wood.

• Class 1: Challenge the smallest student in the class to lift the teacher.

• Class 2: Lift a student against the cabinet.

• Class 3: Launch a water bottle into own hand.

Stage 2: Definitions and diagrams

Use from key questions above.

Stage 3: Worksheet on levers.

Classwork: (attach/link digital resources):

See attached

Assessments: (attach/link copies)

__ Group assessment

__ Observation of process/student work

__ Self-assessment by student

__ Teacher generated assignment

__ Written project

__ Test/Quiz

__ Other: ____________________________________