1. Choose any readily available material, which you think will provide a “slippery” surface.  Your goal is to construct a speedy roller coaster. A standard glass marble will be used as your coaster car.

2. Construct your roller coaster, according to the specifications below. See diagram.

a) The coaster has exactly one hill.
b) Height of the hill (h) is 0.5 meters.
c) Midpoint height of the hill (at 0.5 meters of horizontal distance) is 20 centimeters.
d) Total horizontal length of the hill (l) is 1.0 meter.
e) There is an additional 1.0 meter of level track after the  hill.

3. Conduct ten speed trials, according to the procedure below.

a) Position your marble at the top of your roller coaster.
b) Allow it to roll down the hill without pushing it.
c) Begin timing on a stopwatch when the marble starts rolling.
d) Stop the watch when it reaches the end of the level track.
e) Record the elapsed time, to the nearest 0.1 second on the appropriate Data Collection Page.
f) Compute the speed (rate) the marble traveled, using the formula:
rate = distance / time.  Record your data on the Data Collection Page.
g) Repeat steps a through f, for the remaining nine trials.
h) Compute and record the average speed for your coaster.

4. Data Analysis:  Examine the data posted on the project web page, collected from all of the participants, by clicking on Project Data in the navigation bar.  Look for similarities and differences in the results.  What could account for the similarities?  For the differences?  Which material appears to be the most slippery?

5. Formulate a written hypothesis describing the construction material and track design to use for the fastest roller coaster.  Justify your hypothesis based upon your data analysis.  If you are participating in the competition portion of the project, you will build your coaster using this material and track design.