Invent-a-Wheel: Make a car that rolls down a ramp!

invent a wheelThis workshop develops concepts of gravity and friction by exploring how to get an object to move through experiments with ramps and sleds. By varying the height and surface material of the ramp, participants try to make a cardboard sled slide down a ramp. Participants explore how rollers can reduce friction, and then they will incorporate the rollers into the sled, turning the rollers into wheels and the sled into a car. All worksheets and material ordering information will be provided.

Participants will begin by listing and sorting ways of getting any object to move. Then they try getting small cardboard sleds to slide down ramps. How do the height and surface material affect whether the sled will slide down? To reduce friction, they try rollers, which allow the sled to roll freely down the ramp. However, the rollers separate from the sled at the bottom of the ramp; the rollers keep going, but the sled stops.

To address this problem, participants are provided with wheels and are challenged to add them to their sleds. They then test and troubleshoot these cars, write “How-to” manuals showing how to make one, and customize their cars using craft materials. The workshop culminates in car races, in which participants compare how well their cars travel down large ramps. The curriculum was designed by Early Childhood teachers and has been used extensively in the NYC Public Schools. The materials are inexpensive and the curriculum is available at no charge at

Gary Benenson

Professor, City College of New York

Gary Benenson is a Professor of Mechanical Engineering at the City College of New York, where he has worked for 30 years. For the past 25 years, he has been Project Director of City Technology, which has received four major National Science Foundation grants for curriculum and professional development to support curriculum and professional development to support engineering education in the elementary grades.

Jody Hilton

Science teacher, Marcus Garvey School

Jody Hilton has worked for the New York City Public System for 20 years. She spent 11 years as a classroom teacher in grades 1-3, and 5 years as a literacy coach specializing in Teachers College Reading and Writing Project. She is currently the Science Teacher at PS 44, the Marcus Garvey School in Bedford-Stuyvesant, Brooklyn, NY. She also holds two additional New York State Licenses in the areas of School Administration and Counseling. Jody has been affiliated with City Technology for the past 9 years. She is a member of the team that has created and tested the Fantastic Elastic curriculum.