Washington - The family had been talking about Black History Month over dinner on a recent February weeknight, and Kirstin Cassell, a clinical social worker in Greensboro, North Carolina, had asked her children what their classrooms were doing to celebrate.
But it wasn't until later, after the plates were cleared away and the younger children had wandered off, that Cassell's 12-year-old son admitted he was bothered by something at school.
"I've noticed something," he began, and then told his mom that there were black boys in his class who were consistently getting in trouble with the teacher for goofing around. This troubled him, he said, "because they're not doing any behaviours that are any different than what I do."
In that moment, Cassell says now, several thoughts raced through her mind: that she'd always known her oldest child could be silly in class and that she had wondered whether he might get away with it because he was white. That her 8-year-old son, who is black and adopted from Ethiopia, might find himself in that same classroom in a few years. That she was proud of her seventh-grader for identifying the problem. And that she wasn't sure how to fix it.
"So I told him: You're right, and that's not fair, and we have to figure out what we're going to do about that," she recalls.
It was a scene that would not have played out in her own childhood home. Like many white Americans who grew up in the wake of the civil rights movement, Cassell, 40, was raised with the ideology of "colourblindness," which teaches that it's best to behave as though racial differences simply don't exist and shouldn't be pointed out.
But in recent years - with the rise of the Black Lives Matter movement, as social justice activism has crossed into the mainstream and discussions about race have dominated both national headlines and the vitriolic political landscape - more attention has been focused on the role that white people must play in addressing racism, and more parents like Cassell are trying to learn how to speak to their children about the realities of the world they live in.
"My kids bring it up," Cassell says. "My youngest has talked about the fact that he is not the same color as we are ever since he knew his colours."
It's natural for kids to notice differences between people they meet, says Beverly Daniel Tatum, author of Why Are All the Black Kids Sitting Together in the Cafeteria? and Other Conversations about Race." But the key moment, she says, is what follows - when a child turns to an adult for guidance about what those differences mean.
Tatum often talks about the day her 3-year-old son came home from nursery school and asked, "Tommy says my skin is brown because I drank chocolate milk; is that true?"
"Tommy's not being mean or insulting; he's just trying to figure something out," Tatum says. "So in my response to my son, I said, 'No, your skin is not brown because you drank chocolate milk. Your skin is brown because it has something in it called melanin. Everyone has some, even Tommy has some, but in your school, you are the kid with the most.' "
She'd answered her son's question, she says, but she was left with one of her own: "Now, who is setting Tommy straight? What conversation is happening at his house?"
The theoretical scenario goes something like this: A small white child is accompanying a parent at the grocery store when he notices someone who doesn't look like people he's seen before. So he turns to his parent and says, perhaps a bit too loudly, "Why is that person so dark?"
In this situation, a parent's first instinct is usually a mortified shhhh - "not an explanation," Tatum says. "The child makes an observation, the parent silences the child in a hurried way, and what that says is, 'You're not supposed to notice, and also there's probably something wrong with what you've just called out.'"
A better response? "You could say, 'People come in different colours - like how you have blond hair and dad has brown hair,' " Tatum says. "It doesn't have to be a big deal."