I believe it's so important for kids to read about all different diverse experiences and see all different types of people in illustrations. What is equally important, I think, is to have stories coming directly from people of color, and show kids that anyone can be a writer/artist.
Nigerian author Chimamanda Ngozi Adichie has spoken about the danger of a single story. She says that when she was young, she used to write stories about white people, because that's what she was used to reading. And she's not the only one. I've heard stories from teachers whose students, no matter what their color, only write or draw white people. This is indicative of what we are reading to our kids, both at home and in school. It's not a realistic view of the world and makes some people feel excluded from literature, which is a real shame. We should be exposing our kids to diversity at an early age.
You can watch Adichi's TEDTalk below.