Four years after Mark Zuckerberg made his $100 million donation to help the Newark, New Jersey, school system, most of the money is gone and critics say the city has not turned into the "symbol of educational excellence" he had hoped for.
That's because a silver bullet, no matter how large and well-intentioned it is, won't magically change years of social and economic inequality, Randi Weingarten, president of the American Federation of Teachers, told CNBC's "Power Lunch" on Friday.
"The work we're involved in is not a silver bullet kind of work. You have to engage the community, you have to have a shared sense of what you need to do and then you have to do it," she said.
One of the criticisms of Newark's school reform has been the lack of input from the community, according to The New Yorker, which examined the city's efforts.
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Ken Berger, CEO of Charity Navigator, said while Zuckerberg had good intentions, his generous gift was not very well-thought-out.
"We see this very often, that people start from the heart ... but then when it comes to the question of using the community, engaging the community, sometimes that gets lost and there's a top-down approach that occurs where there's a disconnect with the realities on the ground," he told "Power Lunch."
"Here we had a foundation with only millionaires on it," he added.
Facebook declined CNBC's request for an interview with Mark Zuckerberg.