Cardboard Marble Run STEM Challenge

This easy STEM challenge uses recycled materials you probably already have at home and encourages kids to design, build, test, and improve their own marble run.

The best part? Every marble run is different, which means endless opportunities to experiment, solve problems, and think like an engineer.

The Science Behind It

A cardboard marble run is a simple STEM challenge that uses cardboard tubes, tape, and marbles to explore gravity, motion, energy, and engineering. Kids design, build, test, and improve their own marble run while learning through hands-on experimentation.

Grade Levels: 3-8
Field of Science: Physics, Engineering, Force and Motion
Concepts Explored: Gravity and motion, Potential and kinetic energy, Momentum, Engineering design, Problem-solving skills, Cause and effect, Testing and improving a prototype

👉 Looking for more marble fun? Try our Marble Roller Coaster STEM Project

Supplies

Cardboard tubes (toilet paper rolls, paper towel tubes, wrapping paper tubes, etc.)
Painter’s tape
Scissors
Marbles or small balls
Container for catching marbles

Optional Materials

Paper cups
Paper plates
Small boxes

How To Build A Cardboard Marble Run

STEP 1: Design Your Marble Run

Before you start building, think about how your marble will travel from start to finish.

Ask yourself:

Where will the marble begin?
Where will it end?
How steep should the track be?
Will there be turns, tunnels, or obstacles?

STEP 2: Build The Track

Use painter’s tape to attach cardboard tubes to a wall, refrigerator, door, bookshelf, or large piece of cardboard.

Connect the tubes to create a path for the marble to follow.

cardboard tubes taped to wall for giant cardboard marble run STEM project

STEP 3: Test Your Marble Run

Place a marble at the top and watch what happens.

Does it reach the end?
Does it get stuck?
Does it move too fast?
Does it jump out of the track?

STEP 4: Improve Your Design

Make adjustments and test again.

Engineers rarely get a design perfect on the first try. Testing, redesigning, and improving are all part of the process.

💡 STEM Tip: We love building marble runs on a blank wall because it’s easy to change the height and angle of each tube. No wall available? Try a refrigerator, a door, a bookshelf, or even a large, flattened cardboard box.

Marble Run Ideas

Once you have a basic track working, try adding:

Paper cup funnels
Cardboard ramps
Tissue box tunnels
Spiral sections
Marble jumps
Recycled packaging pieces
Multiple pathways

The more creative the design, the more opportunities kids have to test and improve their ideas.

Think Like An Engineer

Engineers solve problems through trial and error. Learn how to incorporate the engineering design process to extend the project learning.

As you build your marble run, ask:

What happens if the angle is steeper?
What happens if the tubes are longer?
How can I make the marble travel farther?
Which design works best?
What changes improve the marble’s motion?

👉 Want more building challenges? Explore our Engineering Projects for Kids collection.

The Science Behind A Marble Run

A marble run is a fun way to explore physics through play.

Gravity pulls the marble downward through the track. The steeper the slope, the faster the marble moves.

Potential Energy is stored energy. When the marble sits at the top of the run, it has potential energy because of its position.

Kinetic Energy is the energy of motion. As the marble rolls, stored energy is converted into motion.

Momentum helps the marble continue moving through turns, dips, and obstacles.

🔎 Looking for more hands-on science? Explore our Force and Motion Activities, Potential and Kinetic Energy Activities, and Physics Experiments for Kids.

Marble Run Challenge Ideas

Ready for another challenge?

Build the longest marble run possible.
Add three turns.
Create a marble jump.
Design a spiral section.
Build a marble catcher.
Create a run that takes 10, 20, or 30 seconds to finish.

FAQ

Why does the marble move faster on steeper ramps? A steeper ramp allows gravity to pull the marble downward more strongly, increasing its speed.

Why does my marble stop before reaching the end? The track may be too flat, the connections may not line up smoothly, or friction may be slowing the marble down.

What materials can I use besides cardboard tubes? Paper plates, cups, cardboard strips, pool noodles, craft sticks, and recycled packaging materials all work well.

What age is this activity best for? This activity works well for grades 3-8 with adult assistance as needed. However, younger kids will enjoy assisting with the building and exploring with the marble run!

Is a marble run an engineering activity or a science activity? It can be both. Build and improve the design as an engineering challenge or test different variables to create a science investigation.

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Free Marble Run Challenge Sheet

Want to take this activity further? Download our free Marble Run Challenge Sheet and encourage kids to plan, build, test, and improve their own marble run designs while exploring gravity, motion, and engineering.

Explore More Force and Motion Activities

If your kids enjoyed this cardboard marble run, they’ll love experimenting with ramps, motion, speed, gravity, and energy through hands-on STEM activities.

From balloon rockets and LEGO ramp challenges to moving cars and energy investigations, our Force and Motion Activities make physics fun and engaging for kids.

👉 Explore More: Force and Motion Engineering Activities for Kids

Looking For More Engineering Challenges?

Our Engineering Projects Pack includes 80+ hands-on STEM challenges that encourage creativity, problem-solving, and critical thinking with everyday materials.

Want more hands-on STEM ideas that actually work?

Our Classic STEM & Engineering Projects Pack includes 50+ favorite experiments and engineering challenges with printable journal pages, instructions, and easy-to-find supplies. Perfect for classrooms, homeschool, and curious kids who love to build and test ideas.

👉 Explore the Classic STEM Projects Pack here.