The Brooklyn Children's Museum was first opened in 1899 located in two Victorian mansions on Brooklyn Avenue. Founded through the Brooklyn Institute of Arts and Sciences, it was the first museum for children in the country and grew immensely popular. Eventually in 1975, the two mansions that housed the museum were demolished and its current building designed by architectural firm of Hardy Holzman & Pfeiffer Associates was constructed. Moreover, its 2008 renovation prompted another first: the first NYC LEED-certified Green museum. It continues to be one of the nation's premiere children's museum, boasting a permanent collection of more than 30,000 items.