ScienceGrade 3

What Is a Lever? Playground Seesaw Science

A lever is a simple machine: a stiff bar that turns on a point called a fulcrum

Learning Objective

Students will learn that a lever is a simple machine — a stiff bar that turns on a point called the fulcrum — and that where you put the fulcrum changes how much force you need to lift a load, so even a small push can lift something heavy.

What You'll Learn

The thing you're lifting is the load; the push you make is the effort
A seesaw is a lever — push down on your side (effort) and the other side's load goes up
Move the fulcrum closer to the load and lifting gets EASIER — a long arm spreads out the work
Move the fulcrum toward the effort and lifting gets harder but the load moves farther/faster
Everyday levers: bottle opener, wheelbarrow, scissors (two levers!), crowbar, a spoon digging into a tough lunchbox lid
Levers help a small force beat a big load — that's why they're one of the six simple machines

Words to Know

Lever: A simple machine — a stiff bar that turns on a point to help you lift; The seesaw is a lever that lifts me up and down.
Fulcrum: The point a lever rests on and turns around; The middle bar of the seesaw is the fulcrum.
Load: The heavy thing you're trying to lift; The boulder was the load on our seesaw lever.
Effort: The push or pull you make on the lever; My push on the seesaw was the effort that lifted the load.
Simple machine: A basic tool with few parts that helps us do work; A lever, a ramp, and a pulley are all simple machines.
Pivot: To turn on a point; The lever pivots on the fulcrum like a seesaw.

Check What You Learned

Quick Quiz

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What is a lever?

Fun Facts

A lever is a simple machine made of a stiff bar that turns on a fixed point called the fulcrum
Source: NGSS / physics textbooks
Every lever has three parts: the load (the thing being lifted or moved), the fulcrum (the pivot point), and the effort (the push or pull you apply)
Source: physics textbooks / Britannica Kids
A seesaw is a lever — the middle bar is the fulcrum, each rider is a load, and pushing off the ground is the effort
Source: physics textbooks
Moving the fulcrum closer to the load gives your effort a longer arm — a longer lever arm means the same push lifts a heavier load more easily
Source: physics textbooks / NGSS 3-PS2
Moving the fulcrum closer to the effort makes lifting harder but moves the load farther and faster
Source: physics textbooks
Everyday levers include a wheelbarrow (wheel = fulcrum), scissors (two levers pivoting together), a bottle opener, and a crowbar
Source: Britannica Kids / physics textbooks

Lesson Info

Grade 3

2026-11-09

Standards Alignment

3-PS2-1
Plan and conduct an investigation to provide evidence of the effects of balanced and unbalanced forces on the motion of an object — lever effort vs load
TEKS 3.7B
Demonstrate and observe forces that change the position and motion of objects — levers in action
TEKS 3.7C / engineering practices
identify and use simple machines that make work easier
CCSS.ELA-LITERACY.RI.3.3
Describe the relationship between a series of scientific ideas in a text — how fulcrum position changes the effort needed