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Simple and complex machines help us do work with less force, or effort. This unit explains what work is, as well as the relationship between force and distance. It introduces the seven traditional simple machines and how they function. One or more simple machines may be combined to form complex machines capable of doing many repetitive, difficult, complicated, or dangerous tasks. Understanding how various machines work will help students to choose appropriate machines and use them properly.


Supporting Materials

Show Me Only

Additional Reading

Comprehension Support


Science Videos

A Rube Goldberg Machine
Materials Engineer
Using Weights to Balance a Lever

Career Files

Robotic Engineer; Hair Stylist/Barber; Elevator Mechanic

Retelling Rubrics

Nonfiction Retelling Rubric

Vocabulary Cards

Word Work

Word Search; Analogies/Fill in the Blank; Word Sort

Book Assembly