To get some ideas about public service announcements, check out this fabulous PSA from India that uses the gods of India and their vahanas (vehicles) to warn people that they should wear helmets for safety! The PSA was produced by the India Head Injury Foundation, and you can read more about it at Buzzfeed. The gods you will see are Vishnu, Durga, and Ganesha: Vishnu on Garuda, Durga on her lion, and Ganesha on his mouse — but "even those who protect you protect their heads" ... so they wear their helmets when they ride!
And here is one of the most famous PSAs from the 1970s: Keep America Beautiful.
And here's a PSA that went viral a few years ago, Dumb Ways to Die (train safety):
And, of course, there is one of the most famous PSA figures of all time: Smokey the Bear. Read more about Smokey at Wikipedia; he dates back to the 1940s.
"Remember... Only YOU Can Prevent Forest Fires."