Wiggling Ears: The TP Roll Bunny Engineering Project
How do you make a toy bunny with moving ears using only a toilet paper roll?
To make a bunny with wiggling ears, you need to build a simple mechanical linkage inside a cardboard tube. By using a "pull-tab" lever system made from a cereal box or scrap cardstock, you can create a pivot point that allows the bunny’s ears to flop up and down when a paper strip is moved. This project takes about 10 minutes, uses 100% recycled household items, and introduces children to basic engineering and physics.
At Tierney Family Farms, we believe that education should be hands-on and sustainable. We aren't just putting two things together with a piece of tape and calling it a day. We want to build things that actually work. This "Lever Bunny" isn't just a decoration; it’s a machine. It teaches kids that they can manipulate the world around them using the "trash" found in the recycling bin.
Why focus on engineering and family sustainability projects?
In a world of plastic toys that arrive in two days with the click of a button, there is a massive educational gap. Kids often don’t understand how things are put together. When we engage in family sustainability projects, we are teaching two things at once:
- Resourcefulness: You don’t need a store-bought kit to create something cool.
- Mechanical Logic: Understanding how a lever or a pivot works is the foundation for everything from a seesaw to a car engine.
By upcycling a toilet paper roll, you’re also discussing the lifecycle of products. Instead of the tube going straight to the bin, it becomes a tool for learning. This aligns perfectly with our other family gardening and sustainability projects, where we look at how to reuse materials like milk jugs for winter sowing or creating hydroponic systems from scratch.
Image description: High-quality Pixar-style 3D render of a cartoon child character using safety scissors to cut cardboard at a kitchen table with a toilet paper roll, cereal box cardboard, and bunny ear pieces. No text or overlays.
The Junk Drawer Kit: What You’ll Need
Don’t go to the craft store. Seriously. Everything you need for this is likely sitting in your kitchen or your recycling bin right now.
- 1 Empty Toilet Paper Roll: The "chassis" of our bunny.
- 1 Cereal Box (or any thin cardboard): This provides the "bones" for the ears and the lever.
- Scissors: To cut our mechanical parts.
- Tape or Glue: To secure the pivot points.
- Markers or Crayons: Because every piece of engineering needs a little flair.
Step-by-Step Build: The Lever-Action Mechanism
This is where we move beyond "simple" and into "functional." Follow these steps to build the internal linkage.
1. Prep the Ears
Cut two long bunny ear shapes out of your cereal box cardboard. Leave an extra half-inch at the bottom of each ear: this is your "anchor tab." Fold that half-inch tab forward. This fold acts as the hinge.
2. Create the Hinge Point
On the back rim of the toilet paper roll, tape the ears down using those anchor tabs. The ears should be able to flop forward over the top of the tube. This is a basic pivot. If you stop here, you just have a bunny with floppy ears. Now, we add the "motor."
3. The Pull-Tab Lever
Cut a long, thin strip of cardboard (about 6 inches long and 1 inch wide) from your cereal box. This is your lever. Near the top of the toilet paper roll, on the front side (opposite the ears), cut a small horizontal slit. Slide your lever strip through this slit so that most of it is inside the tube, but a "handle" sticks out the front.
4. Connecting the Linkage
This is the trickiest part, but it’s the most rewarding. Reach inside the tube and tape the top end of your lever strip to the base of the bunny ears (just above the hinge).
Image description: High-quality Pixar-style 3D render showing the inside of a cardboard tube bunny with a pull-tab linkage connected to the ears. The mechanism is shown clearly through composition only, with no text, arrows, or overlays.
5. Testing the Physics
Now, hold the bunny by the tube and pull the tab sticking out the front downward. Because the tab is connected to the ears, pulling it down should pull the ears up (or push them forward, depending on your tape angle).
Troubleshooting the "Wiggle"
If the ears aren't moving smoothly, you’re facing a classic engineering challenge: friction.
- If the ears are stuck: Check if the tape is too tight at the hinge.
- If the lever is flimsy: Double up the cardboard strip to make it more rigid.
- If the movement is small: Move the connection point on the ear. The further away from the hinge you attach the lever, the more "travel" the ear will have.
This kind of troubleshooting is excellent for character building activities for kids. It teaches them that the first design isn't always the final design. In our DIY cardboard puzzle guide, we talk about similar concepts of trial and error.
The STEM Behind the Fun: Levers and Linkages
While the kids are busy making their bunny "talk" or "dance" by wiggling its ears, you can drop some knowledge on them. This project uses a First-Class Lever system.
- The Fulcrum: The fold where the ear meets the tube.
- The Load: The weight of the ear itself.
- The Effort: Your hand pulling the tab.
Understanding how to transfer motion from one place (the front of the tube) to another (the top of the ears) is what mechanical engineering is all about. It’s the same logic used in the vertical farm towers we discuss elsewhere, where we have to figure out how to get water from the bottom to the top efficiently.
Image description: High-quality Pixar-style 3D render of several completed toilet paper roll bunny toys displayed on a cheerful craft surface, each with different ear positions. No text or overlays.
Character Building: Patience and Precision
At Tierney Family Farms, we aren't just about growing plants; we are about growing people. Projects like this require a level of precision that "quick crafts" don't. If the slit is too wide, the lever wobbles. If the tape isn't centered, the ears move crookedly.
Encouraging your child to "measure twice and cut once" is a life skill. It’s the same patience required when testing old seeds to see if they’ll still sprout. You can't rush the process, and the reward is in the functioning final product.
Sustainability: The Cereal Box Advantage
Why do we insist on using cereal boxes? Because cardstock from the store is expensive and unnecessary. Cereal boxes are made of "chipboard," which is incredibly resilient and has just the right amount of flex for mechanical toys.
By choosing to use what you have, you are participating in a larger movement of family sustainability. Whether you're growing vegetables indoors year-round or building a bunny toy, you’re reducing waste. It’s a small step, but it’s a meaningful one for a child to see that "trash" can be transformed into a toy they actually enjoy playing with.
Image description: High-quality Pixar-style 3D render of two cartoon child characters celebrating their completed toilet paper roll bunny project in a cozy room with plants. No text or overlays.
Final Touches and Customization
Once the mechanism is working, it’s time to decorate.
- Whiskers: Use old thread or thin strips of leftover cardboard.
- Face: Use markers to give your bunny a personality. Is it a grumpy bunny? A sleepy bunny?
- Fur: If you have cotton balls or old fabric scraps, you can "upholster" your engineering project.
Just remember: don't let the decorations interfere with the moving parts! This is the most common mistake in engineering: adding "fluff" that stops the machine from working.
Ready for More?
The Wiggling Ear Bunny is just the start of our "Tierney-Tough" Easter series. If your kids enjoyed the challenge of building a moving mechanism, they might be ready to dive into some of our more advanced science projects. From magic milk experiments to building a 10-minute hydroponic system, we have plenty of ways to keep those hands busy and those brains growing.
Keep building, keep growing, and keep it Tierney-Tough!
References:
- Tierney Family Farms, "Educational STEM Projects for Families," 2026.
- Engineering for Kids, "Understanding Simple Levers and Linkages," 2024.
- Sustainability Quarterly, "The Impact of Upcycling in Early Childhood Education," 2025.