MAPLEWOOD, N.J. — Few things are more awesome than listening to kids playing on the playground. There’s magic in that mix of laughter and exhausted breaths — giggle, pant, giggle.

Just the other Saturday at Maplewood’s Memorial Park, I was watching my 5-year-old playing with his friends from day care. The kids have just started kindergarten and are now split up among four schools. Some industrious mom had the idea to get them together again.

It was a great idea. It was also the moment when I saw the messy birth of my son’s otherness.

They were playing on one of those spinning things — you know, the one where kids learn about centrifugal force and as a bonus get crazy dizzy. They were having a blast.

“Only white people,” said a little girl.

I heard it, but I wasn’t quite sure that’s what I heard.

“Not you, you’re black,” said the girl, reaching out to touch my son. “You’re not white. Only white people can play.”