Your goal is to design a roller coaster that’s both fun and safe to ride!

A true hill needs both an upward and a downward slope. A tall downward ramp or slide with no slope leading up to it doesn’t count! You can include both hills and ramps in your design, though. Think about how you’ll get the marble moving. What will it take to get it going up a steep hill?

For example, would it help to give your track high walls or railings? Can you create some sort of gutter or safety net to catch the marble in case it falls off? Try to guess which parts of the track are possible danger zones. Do you think your marble is more likely to fly off track going uphill or downhill? What about at curves in the track?

For example, what if you put a barrier at the end of the track? How can you prevent the marble from bouncing over the barrier?

If you want, you can use your pencil or a marker to mark on the board where you want to put different parts of the track.

For example, you could push the sticks into the foam board, or create clay “feet” to help them stand. Do some parts of the track need extra support? How can you make your support pieces shorter or taller? Remember, you need at least 1 hill to be 6 inches (15 cm) high or taller, so use your measuring tape or ruler to check the height of your hills.

Does it help to use longer or shorter pieces of foil for some parts of the track? Do you think the pieces of your track are sturdy enough to hold up the marbles? What can you do to make them stronger?

For example, maybe you could use pieces of clay to support lower bumps or hills on your track, or construct a safety net for your marble to fall into using pipe cleaners.

For example, if you’ve just built a big hill, try sending your marble over it. Does it have any trouble getting up the hill? What can you do to give it a better running start?

How is this different from a real roller coaster? How is it the same?

It can be helpful to have someone else hit the timer while you start the roller coaster. If you don’t have a stopwatch, try counting in “alligators” to count the seconds. If you say “alligator” after each number (“1 alligator, 2 alligator,” and so on), it will take you about 10 seconds to get to 10.

For example, does your marble go faster when it’s going uphill, or downhill? What about bends in the track?

Once you come up with an idea, put it to the test! Try making adjustments to your track and see what happens.