If you’re looking for a fun engineering challenge for kids, this marble run is just the thing! At our house, it seems like we are always experimenting with marble runs. I especially love it when we can make a fun marble run with materials from around the house.
Here’s a marble run to make with straws, hot glue, and a cardboard box. We highly recommend this activity! Perfect for a rainy day or a quiet afternoon. This would also be a great STEM challenge to do with a class or after school club.
This post was updated in February 2022.
- Large, shallow-ish cardboard box
- Straws – either paper or plastic
- Glue gun
- Plastic bottle caps
Paper straws and traditional plastic straws work equally well for this project. Paper straws are obviously beneficial because they are biodegradable, but there is a significant difference in price. If paper straws are just not in your budget, plastic ones work great. We used a combination of both.
We used a low-temp gun since it’s safe for kids to use themselves. (Always be careful, and of course you know whether your child is ready for this or not!)
Marble Run or Marble Maze?
There are different ways to go about building this marble run. I’ve seen people use boxes and straws for marble mazes. You tilt the box back and forth to make a marble roll through a maze made out of straws. That’s fun to do, but for this project we decided to prop up one end of the box with books and create a course for the marble to roll down. You can do either one!
Start Building at the Top… or Bottom!
It doesn’t matter which one! We started building at the top, but starting at the bottom works well too.
We didn’t draw up a plan before making our marble run. We did, however, test out the run after we added each piece. We also took turns holding the next piece in place and releasing the marble to make sure it would do what we wanted it to before gluing it down.
If you make the ramps too steep, the marbles will careen out of control. But if they’re not steep enough, the marble may get stuck or just not gather enough momentum.
One good thing, though, is that you can always adjust the tilt of your box. That can help with ramps that are too steep.
Build More Than One Path Down
Give your marble run two starting points! It makes it much more interesting. Our marbles did not take the same path down each time. Even if we started them on the right side, they might finish on the right or jump over to the left.
We used some straw segments to make a landing spot for the marbles. We used two layers of straws for this to make the walls a bit higher.
The plastic lids were really a fun addition to our marble run. We positioned them where the marbles would HAVE to go around them. Fun to watch!
Want more Marble Run STEM Challenges?
See a similar marble run on a MUCH larger scale here – Giant Cardboard Box Marble Run
For something different (and super creative), try these Play Dough Marble Run Ideas!
Build an Epic LEGO Marble Run – this is SO much fun.