Boston Children's Museum
308 Congress Street, Boston, MA 02210
617-426-6500
© Boston Children’s Museum 2024
Website Design by JackrabbitChildren get too few chances to experiment with materials and to design and build objects of their own creation. These Raceways and Roller Coasters activities allow your students these opportunities, and engage them on many different levels as well. Building these tracks and rolling marbles down them help children to develop problem-solving and teamwork skills and touch upon some basic principles of physics like energy, acceleration and momentum.
See the Purchasing and Preparing Pipe Insulation PDF (click here to open) for instructions on finding and prepping the insulation. This pipe insulation will serve as the tracks for all of the marble-rolling Raceways & Roller Coasters experiments – and make sure to try all of the Raceways & Roller Coasters activities. The insulation comes in tubes, which you will cut in half lengthwise, so that you have two long U-shaped troughs to roll marbles down.
Depending on where you purchased it, you may have 3-foot or 6-foot pieces of pipe insulation. Each team will make two 6-foot tracks in this activity, so if you have 3-foot pieces, the first design challenge that your students will face will be how to attach the tracks together effectively. Masking tape works pretty well, and each team should have a roll, but let them experiment with connection methods and have them share their discoveries with each other rather than showing them how to do it.
Ask your students if any of them have ever been on a bicycle, scooter or skateboard before. Did they ever come across a hill? What did they notice about riding down these hills? Did they travel faster, slower or the same speed on different-sized hills?
Tell your students that they will be building 2 straight tracks per team and racing marbles down them. The tracks will be the same length, but you would like them to try all sorts of different angles for the tracks to see if this makes a difference in how quickly the marbles travel down the track. Hold a piece of insulation up for them and show them what you mean by different angles, first holding the track almost parallel with the ground, then showing them a steep angle (nearly pointing up and down). Ask them if they think the marble would travel differently down one of these tracks vs. the other.
Show them that they can change the angle of their track by just changing the height of the starting point of the track — the end of the track can remain in place.
Can you figure out if the angle of a track makes a marble travel faster or slower?
After 5–10 minutes, bring your students together to talk about what they’ve done. Have each team share their process. How did they set up their experiment? How did they know at which height their track was starting? What did they do to ensure that they were conducting a “fair test”? In this activity, a “fair test” is one where each marble is facing the same conditions in the experiment. Look for children who were holding their tracks rather than resting them on tables, chairs, etc. How could they be certain that they weren’t moving the tracks, shaking, changing the height, etc. while they were holding them? Can they be certain, if 2 students were holding the 2 tracks, that they were holding them exactly the same? How could they guarantee that the track was staying in a consistent position? Let them come up with their own thoughts as to how to ensure a fair test, but look for responses that suggest resting the track on something stable like a table, chair, pile of books, etc.
Send teams back to experiment some more and make sure that they are recording their observations. When the session is nearly over, bring the teams together again to share their results. Which starting height (angle) caused the marble to roll the fastest? Which height/angle caused the marble to roll the slowest, but still complete the run? Was there a point at which the angle was too steep or not steep enough?