Muscle Mission Guide Muscle Mission Guide
30-Minute Lesson Plan • Grade 3
BIOLOGY
Mission Objectives
Identify the difference between voluntary and involuntary muscles.
Explain how muscles work in pairs (flexing and relaxing).
Understand that the heart is a special, powerful muscle.
Key Vocabulary
Voluntary
Muscles you choose to move (like your arms).
Involuntary
Muscles that work on their own (like your heart).
Contract (Flex)
When a muscle gets shorter and tighter.
Relax
When a muscle gets longer and thinner.
Gear Needed
Power Pump Slides
Muscle Maker Worksheet
Pencils & Colored Pens
A clear space for students to stand and move
Mission Timeline (30 Minutes)
The Hook: Mystery Movers
0-5 MIN
Instruction: Ask students to sit perfectly still. Ask: "Is anything in your body still moving even though you aren't?"
Introduce the idea that muscles are the "engines" of our bodies. Some we drive, some drive themselves!
The Discovery: Slide Briefing
5-15 MIN
Instruction: Use the Power Pump Slides to define Voluntary vs. Involuntary.
Demonstrate the "Bicep Pair" – show how when one pulls, the other rests. Have students touch their own biceps while bending their arms.
The Training: Muscle Maker Lab
15-25 MIN
Instruction: Students complete the worksheet independently or in pairs.
Circulate and ask: "Is your heart a voluntary muscle? Why or why not?"
Debrief: Flex Off
25-30 MIN
Rapid fire game! Call out an action (blinking, running, heartbeat, digestion). Students flex their muscles if it's voluntary, or stand like a statue if it's involuntary.
Pro-Tips for Success
Keep it Moving:
3rd graders learn best through movement. Every time you mention a muscle, have them wiggle it or touch it!
Differentiation:
For students who finish the worksheet early, ask them to list 5 "hidden" muscles we use for things like smiling or talking.
Power Pump Slides POWER PUMP
The Muscular System Mission
The Body Engine
Muscles are the engines that move your body.
You have over 600 muscles in your body!
Running
Smiling
Breathing
Action
Life
Expression
Movement
Two Big Bosses
Who controls your muscles?
Voluntary
Muscles YOU decide to move! Your brain sends a signal to move.
Example: Waving hello
Involuntary
Muscles that work automatically! They never stop, even when you sleep.
Example: Heart beating
The Power Pair
Muscles NEVER push.
They only PULL.
To move a bone back and forth, muscles must work in PAIRS.
1. CONTRACT
Gets shorter and tighter
2. RELAX
Gets longer and thinner
FLEX OFF!
THE RULES:
1
I name an action.
2
If it's VOLUNTARY, flex your arms!
3
If it's INVOLUNTARY, stay perfectly still.
Muscle Maker Worksheet Muscle Maker Lab
Part 1: The Sorting Station
Name:
Date:
1. MISSION: SORTING STATION
Mission Brief: Decide if these actions are Voluntary (You decide to move) or Involuntary (They work automatically).
Waving Hello to a friend
Your heart pumping blood
Kicking a soccer ball
Digesting your lunch
Running away in tag
Blinking to protect your eyes
Remember: Some muscles work both ways, but if your body does it automatically to keep you healthy, it's involuntary!
Muscle Maker Lab • Page 2
Name:
2. MISSION: THE SUPER MUSCLE
The Heart
Your heart is the most hardworking muscle in your body. It is an involuntary muscle.
Why is it important for your heart to work automatically without you thinking about it?
Did you know? You use about 200 muscles just to take one single step! MISSION COMPLETE
Muscle Maker Answer Key Answer Key
Part 1: Sorting Station
1. MISSION: SORTING STATION
Waving Hello to a friend Voluntary
Your heart pumping blood Involuntary
Kicking a soccer ball Voluntary
Digesting your lunch Involuntary
Running away in tag Voluntary
Blinking to protect your eyes Involuntary
Answer Key • Page 2
2. MISSION: THE SUPER MUSCLE
Sample Response:
"It is important because we don't have to remind our heart to beat. If it were voluntary, we would have to think about it every second, and we couldn't sleep because it might stop! Having it work automatically keeps us safe and alive without any effort."
Key points for grading:
Mentions that we don't have to think about it.
Mentions survival or keeping the body alive.
Mentions that it works while we sleep.
