The original idea is super easy, but really you can't control the tracks within the box limits. I think being modifiable gives kids the opportunity to apply more scientific principles, mainly the transfer of energy.
Transfer of energy recap:
-Items that start above the ground have potential energy since they can potentially fall to the ground.
-Once the items start falling, they lose potential energy and gain kinetic energy (kinetic is a fancy term for motion).
-Once there's no more potential (ie. no place more to fall), ideally all of the energy is kinetic and will continue in motion until other forces act on it. Other forces can include things like friction or other obstacles.
Here's what I came up with while J was supposed to be napping:
|Cereal box and toilet paper marble tracks|
I took a cereal box, opened it to flatten it carefully. I stuck one of the longer/larger sides of the box out behind as a base of support. I then taped the other sides so the other longer/larger side sticks mostly up. I did slightly angle it back to make sure marbles don't fly off the front.
I then cut toilet paper tubes in half as the tracks and taped them to the box with painters' tape for the marble ramps. The good thing about painters' tape is that you can reposition it a few times without ruining the tape or the box, yet it's still strong enough to hold up the tubes and marbles, allowing you to modify your designs. Feel free to test your tracks as you build.
Then tape a small paper cup at the end of the track to catch the marbles. I put a cup on top too to hold the marbles before their release.
Here's J demonstrating how it works, one marble at a time.
Work with your younger kid to make the design. If you have an older kid, let them try their designs alone. Did your design work? If not, how can you modify it so the marble tracks so the marbles don't fly out?
---Think angles of the tracks it jumps to or having backboards.
How many marbles can you release at once? How many marbles make it in the cup from your initial release?
Do bouncy balls work in your track? How do they differ in your track from the marbles?
Does the shooter marble work on your track? If not, why do you think it acts differently than the littler marbles.
After my model track became boring, Big J and I worked with Little J to make his own track. He made his turn around the box (a challenge, for sure!)
If you think your box design is ugly brown, feel free to decorate it with paint and markers.
Happy marble tracking :-)