I'm Celeste Headlee and this is TELL ME MORE from NPR News. Michel Martin is away. Coming up, we take a closer look at iconic public service ad campaigns like Smokey Bear and McGruff the Crime Dog. And while everyone knows the good causes they promote, do we know if they actually work? We'll hear more about that just ahead. First, though, we talk about a new initiative that's taking a leap to bring diversity to the world of ballet.