Nicole Eisenberg’s older son has wanted to be a star of the stage since he was a toddler, she said. He took voice, dance and drama lessons and attended the renowned Stagedoor Manor summer camp for half a dozen years, but she was anxious that might not be enough to get him into the best performing-arts programs.

So Ms. Eisenberg and others in Bloomfield Hills, Mich., the affluent suburb where she lives, helped him start a charity with friends that raised more than $250,000 over four years.

“The moms — the four or five moms that started it together — we started it, we helped, but we did not do it for them,” Ms. Eisenberg, 49, recalled. “Did we ask for sponsors for them? Yes. Did we ask for money for them? Yes. But they had to do the work.”

She even considered a donation to the college of his…