The system is looking for short, entertaining YouTube videos and really short, entertaining Vine videos showing off how to use the bikes in a safe way.
"We're looking for creative Chicagoans to help remind Divvy riders how to be safe through short, entertaining safety videos," said Chicago Department of Transportation Commissioner Gabe Klein in a statement.
The winner of both categories will win a five-year Divvy membership. An annual membership costs $75.
Twenty-five runners-up will win a helmet, a T-shirt and five 24-hour passes each.
All videos must show one of the Chicago blue Divvy bikes and address at least one of the following safety topics: walking bikes on the sidewalk, wearing helmets, planning routes and navigating city traffic.
Entries must be submitted via Divvy's website by 5 p.m. Monday, Sept. 30.
Since the program's June launch, unofficial Divvy videos have popped up on YouTube showing everything from how to dock a bike in a station to what sorts of handbags are compatible with Divvy's baskets.
One producer stuck a camera to himself and uploaded several videos of him riding the bikes around town.