"The Power of Children Campaign" was announced publicly last June, and has already collected $69 million in gifts and pledges.
The grant from Kresge, based in Troy, Mich., requires the museum to raise another $5 million by Dec. 31. The museum said it would use the grant toward its ongoing renovation and expansion.
Work started last year on a $15 million upgrade of the museum's Illinois Street entrance. Plans call for a new walkway over Illinois Street and an expanded entrance.
The Power of Children Campaign will pay for building expansion, exhibits and annual operating expenses.