Wolf, Bear and Webelos Cub Scouts all have requirements or electives that involve bicycles.
(Wolf Requirement 9d - road safety, 9e - bike safety; Bear Requirement 14 Ride Right - bike and road safety, basic flat tire repair, etc.; Webelos Handyman 6 - bike maintenance, 7 - bike chain lubrication, 8 - bike tire inflation.)
Naturally, a pack bike rodeo is a great way for all the Cub Scouts to fulfill these requirements. Bike races/obstacle courses are a must, but so are the traffic cones to guide the riders. I have seen real traffic cones in various sizes at the local home improvement store for anywhere from $7.00 a piece to $40.00 a piece. That's too spendy for a once a year event.
Go coneless? Absolutely not.
This takes a few weeks of collecting but it's a good way to go. Those milk jugs your kids empty in a matter of days/hours? There you go. I make sure I give them a good cleaning with dish soap right as soon as the milk is gone and allow to thoroughly dry. Then a quick application of fluorescent spray paint does the trick. I painted almost 20 of these last year and still had enough in the paint can this year to do a dozen more. If your kids drink milk anyway this is the cheapest way to go.
Oh. Your family is lactose intolerant? Allergic to spray paint? Okay, there is always the gallon orange juice jug.
Have your Vitamin C and your traffic cone too!