When I was a little kid, I had this children's book that, depending on how you look at it, either scarred me for life or taught me some very valuable lessons.
The book had all these short stories featuring distinct moral lessons -- look both ways before crossing the street, don't talk to strangers, etc. But the stories were REALLY detailed, and the illustrations accompanying them were REALLY gruesome. Like, Fred the Fox didn't look both ways, and now he's mangled in the street, with bones sticking out of his arms and legs.
Or I remember one about a little wolf (like, you know, Wally the Wolf or something) who stuck his finger in an electrical socket. There was a photo of him (I swear to God I think he was dead), with, like, smoke coming off him because he had been electrocuted to death.
And another one about Hilda the Hippo who couldn't learn to use the toilet. Her hippo parents held up her poopy diaper (yes, with accompanying illustrations) in front of all her friends, and Hilda was so embarrassed that she started learning to use the potty.
Anyhow, obviously the book did the trick in terms of making a lasting impression.
Looks like they've been around for a few months, but if you haven't seen them, be warned! They really are not for the faint of heart.
So...think we should have ads like these in the U.S.?