Joseph VanderWaag still remembers the question written on the chalkboard the day he realized how he became the only black boy in his class.

How does Black History Month affect you?

The students in his eighth-grade social studies class were supposed to write their answers in their journals, but no one did. When the teacher called on several to discuss the question, they responded mostly with shrugs and silence.

None of that surprised VanderWaag. He hadn’t expected his classmates to have a connection to black history. A picture from his kindergarten class shows him with 14 other boys, their tiny arms locked around one another. His is one of two brown faces in the group, and not long after the photo was taken, the other boy suddenly stopped coming to school. VanderWaag asked about his friend — Where did he go? What happened? — but he never got answers from adults, who either couldn’t or wouldn’t give them.

In the years that followed, he grew used to classmates reminding him he was different. Some students called him “Blackie.” Others called him worse. He was in fifth grade the first time he was called the n-word.

As VanderWaag sat in his social studies class that day, he wondered why his teacher had picked a question that seemed so irrelevant to most of the class. Then that teacher pulled out a newspaper article and said, “This is how Black History Month affects you. . . . This is happening in your town.”

The article was about the other boy’s family.

Finally, VanderWaag had his answers. The family had left their Long Island town, but not by choice. They had been driven out by hate.

The article’s headline read: “Refugees from racism: After flood of hate mail, interracial Smithtown family relocates.”

I know the headline because I wrote the article.

The hate that that family experienced and that a boy felt in their absence didn’t happen in a distant era. It happened in VanderWaag’s lifetime, and he is only 20.

I knew nothing about VanderWaag until a few weeks ago when he emailed me to tell me about that day. He describes it as a pivotal moment in his life, one that led him to become “a proud social justice warrior,” fighting not just for himself, but also for others.

I sent a thoughtful reply to his email and moved on — or so I tried.

My thoughts kept coming back to him. I kept wondering what it must have been like to be the only child of any race in a classroom and how his life could have gone in so many different directions. I also wondered what happened to that other family and whether they knew their decision to share their story had caused a ripple that slowly grew into a wave that washed over this boy years later as he sat in class.

Most of the time when we talk about activism, it is in its grandest form: People standing on stages rallying the masses. Or being led to jail in handcuffs because they stood up for their beliefs. Or running for office, despite having no political experience, because they hope to make a difference.

I love those stories. They are inspiring and powerful.

They are also often, as VanderWaag’s life shows, the result of many other actions taken by people who have never stepped onto those stages or felt the weight of those handcuffs or worn out shoes knocking on constituents’ doors.

Sometimes, they simply spoke up.

I wrote four articles for Newsday about Lois Fuchs, who was black, and her husband, Mitchell Fuchs, who was white and Jewish. They had received hate mail for months when a piece of paper finally pushed the couple to pack up their home and leave with their seven children.

The typed note read, “Where’s Hitler when you need him?”

I called Mitchell Fuchs recently to find out what happened to his family after they left. He said there is no escaping racism, but they have had a good life in North Carolina. His children are now between the ages of 13 and 22.

When I explained how his family’s story had pushed VanderWaag toward social activism, Fuchs said he hoped the young man’s actions would have the same influence on someone else.

“I’m glad it got someone to do something other than shake their head,” Fuchs said. “You know what a trickle of water is? A trickle of water is the Grand Canyon.”

Alvin Poussaint, a psychiatrist who has written books on black children, said VanderWaag could have responded to the racism he experienced in many ways.

“The public should appreciate the terrible stress and trauma this puts on a young black person or in this case a young black male from an early age,” Poussaint said. “They have to try to cope with it, and many of them are not successful and are destroyed because of it, because of the racism, and turn out to be antisocial.”

VanderWaag, he said, was able to see “the systemic side of it” and say, “It isn’t just about me; it’s about everyone like me, and I can help myself by helping others.”

Now a college student, VanderWaag volunteers with two political campaigns, organizes March for Our Lives events and has spoken publicly about his own experiences. He also received an EMT certification and volunteered for a while with his local fire department. He said he left after a year in which he was called “EMT chocolate” and “Winston,” the name of the black Ghostbuster.

For a while, VanderWaag said, he internalized all that was thrown at him. Now, he said, he is trying to have real conversations that may not be politically correct but are productive. He is a 6-foot, 200-plus pound openly gay black man, and he knows that makes some people uncomfortable. He wants to talk about that.

“Ask me, ‘Is it racist if I do this? Is it homophobic if I do this?’ ” he said. “Ask me. Fire away. Ask me these questions, because they need to be talked about.”

He’s right, because there’s no telling how your speaking up today might affect someone tomorrow — or even years from now.

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