MISSION VERIFIED
Classroom tested. Teacher designed. Safe at home.
Designed by Darin Carr (BScDip Ed)
Practising NESA accredited
Australian Science Teacher
★ 30+ years of classroom experience
MISSON PROGRESS
48
young scientists have completed this mission.
I'VE COMPLETED THIS MISSION
Click to let us know you have completed this mission
LATEST TEACHER FEEDBACK
No feedback yet for this experiment. Use it with your class and let us know how it went!
HELP IMPROVE THIS INVESTIGATION
USE THIS WITH YOUR CLASS OR AT HOME?
We would love to hear your feedback.
Before you investigate... watch the mystery
MISSION HOOK
Professor Picklebottom and the team are travelling and collecting amazing science mysteries.
✔ Coming in Term 1 2027
Share the science! Tag @the_crazy_scientist on Instagram
— we love seeing your experiments!
Mission Equipment
Gather your materials and get
ready for an amazing mission!
· 1 large zip lock bag (sandwich or freezer size)
· Water
· 3–5 wooden skewers (the pointier the better!)
· A tray or outdoor space — things WILL get wet!
Let’s Investigate
Follow the missions steps below to solve the mystery.
1
Prepare Your Challenge
Fill your zip-lock bag about ¾ full with water and seal it tightly.
Think Like A Scientist
How many skewers do you predict your bag will survive?
□ 1–3
□ 4–6
□ 7–9
□ 10+
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
2
The First Test
Push one skewer carefully through one side of the bag and out the other side.
Watch Carefully
What happened?
□ Water leaked immediately
□ Only a few drops leaked
□ No water leaked
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
3
Gather Evidence
Add a second skewer, then a third.
Keep counting.
Look For Patterns
As more skewers are added:
□ The bag still doesn’t leak
□ Small leaks begin to appear
□ The bag stretches
□ The bag feels weaker
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
4
Find The Limit
Continue adding skewers one at a time.
Keep a careful count.
Data Question
How many skewers survived before the bag failed?
My result: ______ skewers
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
5
Solve The Mystery
Observe what happens.
What happened?
□ The bag survived
□ Water leaked out
□ The bag burst
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
1
Big Title
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
1
Big Title
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
1
Big Title
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Gather your materials and get
ready for an amazing mission!
1
Big Title
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
1
Prepare Your Challenge
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
1
Prepare Your Challenge
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
1
Big Title
Gather your materials and get
ready for an amazing mission!
PREDICT
OBSERVE
EVIDENCE
ASK
SAFETY
TIP
PREDICT
Professor Picklebottom
The Magic Skewer
Imagine pushing a sharp wooden skewer through a bag full of water.
What would happen?
Most people expect a giant splash.
But this mystery bag has a surprise waiting.
Your challenge is to discover how many skewers it can survive before it finally bursts.
Make a prediction, collect evidence and look for clues as you investigate.
Ages
5-12 yrs
Duration
min
10
Difficulty
Easy
Stage
Stage 2-3
Cite this resource
Created by Darin Carr (BSc, DipEd)
NESA Accredited Teacher · Chemistry & Physics Specialist · 30+ years in-class teaching
Resource Version: 1.0
First Published:
Last Updated:
9 Apr 2019
3 July 2026
The Crazy Scientist LAB Learning System™
Every experiment follows The Crazy Scientist Lab Learning System™ — a simple way to help kids think like real scientists.
We
-
LINK to what they already know,
-
ACTIVATE curiosity through hands-on discovery
-
BUILD understanding that actually sticks.
You already know what happens when you poke a hole in a water-filled bag.
Water leaks out.
So why didn’t that happen this time?
Scientists often discover something surprising when an experiment doesn’t behave the way they expect.
This mystery starts with a simple question:
Why can a bag survive a skewer but not survive removing one?
As you pushed more skewers through the bag, you probably expected the leaks to get worse.
Instead, the opposite happened.
The bag kept holding water.
That tells us something important:
The skewer wasn’t simply making a hole.
Something else was happening around it.
Look closely at where the skewer enters the bag.
What do you notice?
Is water leaking around the skewer?
Does the plastic seem stretched?
What changes when the skewer is removed?
Scientists look for clues before jumping to conclusions.
Zip-lock bags are made from a material called polyethylene.
This material is made from millions of tiny flexible chains called polymers.
When a sharp skewer passes through the bag, it doesn’t cut the polymer chains apart like scissors.
Instead, many of the chains slide aside and stretch around the skewer.
The plastic grips tightly around the wood, creating a seal that stops most of the water escaping.
When the skewer is removed, that seal disappears.
The opening is now exposed and water can flow out.
That’s why a bag can survive many skewers—but often leaks the moment one is pulled out.
"Want the full teacher guide? The Crazy Scientist Lab includes classroom delivery tips, how to manage the WOW moment, differentiation for Stage 2 & 3, — ready to teach tomorrow."
Think Like a Scientist
Scientists don't just do ONE experiment; they change one part of the experiment (independent variable) and then see how it affects another part of the experiment
(dependent variable)
Change ONE variable and test again.
What happens if you push the skewer in slowly instead of quickly?
What happens if you use a thicker skewer — or try one that isn't as sharp?
Dr Puddledrip’s Science Tip
🧪 Try it! Change ONE thing and test again. What did you discover?
Want to go deeper? Tap a section below to explore. ▼
The Science Behind It
Why didn’t the water leak?
When you pushed the skewer through the bag, something surprising happened.
Instead of creating a large open hole, the plastic stretched tightly around the skewer.
This helped stop the water from escaping.
The bag could even survive several skewers before it finally failed.
Scientists Say…
Some plastics are made from long, flexible molecules that can stretch and move without breaking apart.
This is one reason the bag was able to hold water even after being pierced.
But that’s only part of the story…
Why did some bags survive more skewers than others?
Why does removing a skewer often cause a leak?
Would the same thing happen with a pencil, straw or metal rod?
Scientists keep asking questions long after an experiment is finished.
You Might Also Like
Teachers & Homeschoolers: Print-ready HD versions of this Science Behind It poster and companion G&T Challenge Card are available inside The Crazy Scientist LAB.
Extension: HPGE / Gifted Learners
Teachers & Homeschoolers: Print-ready HD versions of this Science Behind It poster and companion G&T Challenge Card are available inside The Crazy Scientist LAB.
Vocabulary
Polymer
A material made from long chains of tiny particles that can bend, stretch, and change shape.
Flexible
Able to bend or stretch without breaking.
Variable
One thing that is changed during an investigation to see what effect it has.
Know a parent or teacher who'd love this? Send it on! 👇
READY TO TEACH THIS
TOMORROW?
Running the experiment is easy; however, teaching it well is another challenge.
Teachers often ask:
How do I adapt this for Stages 1,2 or 3?
What misconceptions will they have?
What syllabus outcomes does it cover?
What do I do with fast finishers?
How do I structure this for a full class?
What do I say when they ask WHY?
BUILD AROUND THE LAB LEARNING SYSTEM™
Every resource is designed using our teaching framework.
Inside The Crazy Scientist LAB
Everything you need to confidently teach science tomorrow.
Opening early 2027. Join the Founding Member Waitlist
Try Another Crazy Experiment
Keep the science going with these fun experiments
Stage 1-3
081
MISSION
Water Bug Challenge
Can You Discover How Many Water Bugs a Pond Can Hold?
EASY
EASY
Have you ever seen tiny insects walking across a pond without sinking? Essie noticed this too! Now it’s your turn to investigate how many water bugs the water can hold before its invisible skin breaks.
Stage 2-3
080
MISSION
Tiny Trebuchet
Can you launch an object farther without making your catapult any bigger?
EASY
EASY
Have you ever wondered how people launched heavy objects hundreds of years before engines, rockets or electricity? Engineers had to solve a huge problem. Today it’s your turn! Let’s build a tiny trebuchet, then see if we can improve its design to launch even farther.
Hands-On Science Workshops
Interactive STEM experiences aligned to the NSW syllabus.
