Quercetti Skyrail Mini Rail Rollercoaster – 150 Pc Marble Run with 26 Feet of Track – Building Fun Incorporates Principles of Physics (Made in Italy)

Amazon.com Price:  $29.29 (as of 20/10/2019 06:55 PST- Details)

Build marble runs spanning up to 26 feet long! Children can follow the illustrations in the manual or invent many other configurations, freely expressing their creativity.
A truly unique marble run! Watch the marbles accelerate down steep slopes, climb uphill almost to a stop, roll quietly along flat plateaus, before racing down another chilling plunge at full speed. 
Ideal for demonstrating principles like velocity, acceleration, gravity & friction. Includes marbles of 2 different diameters and weights to experiment the effect of physics forces along the track.