Supplies: large dandelions, hair spray and spray paint (red, white and blue)
Go find some large dandelions.
Before cutting the large dandelion, spray with hair spray. As an experiment I tried both the pump and aerosol and found no significant difference. However, if you are letting a young person apply the hairspray...you might want to go with the pump as you don't have to worry about the aerosol spray blowing the dandelion to smitherings (speaking from personal observation, of course). The hair spray will help you to safely transport your dandelions back home.
Then....you can spray your dandelions with spray paint. I chose red, white and blue in anticipation for the upcoming 4th of July. But whose to say you couldn't spray a bunch with hair spray and set aside. Then color according to the celebration....Halloween (orange and black), kids party (pink, orange, purple).......hmmmm. I better go get some more!