I recently came across a picture book that addresses the topic playfully.
The cover of The Little Bit Scary People, written by Emily Jenkins and illustrated by Alexandra Boiger, depicts a large, mean-looking shadow looming on the street. The image piqued my 4-year-old son's interest, while the "little bit" in the title assured him the book wouldn't be super frightening.
In the story, a young red-headed girl encounters a long list of "shady" characters, from a mohawked punk rocker boy to a persnickety bus driver to a strange classmate who munches on her pencil and mutters to herself.
But as soon as we're introduced to each person, we find a different view, on the following page, of who they really might be.
On the next page, we see the woman looking relaxed and carefree in a track suit. "But I bet, when school gets out, she goes for a jog, listening to show tunes on her headphones. She sings as loud as she can and doesn't care if people hear."
For preschoolers and young elementary students in particular, it's comforting to imagine that people who might appear gruff or odd looking have families and pets and hobbies.
A clever twist comes toward the end of the book: We discover that the leather-clad, trash-can-kicking teenager outside the candy store is actually the narrator's sister, and the policeman who admonishes people for jaywalking is her father.
"Some people are a little bit scary," the book echoes on its last spread. "But then, sometimes (most times, maybe, I think) sometimes they really are not."
Or, as my almost 7-year-old daughter, Mira, put it after we finished the book: "People are all weird."