Brooklyn Children's Museum celebrated the opening of its newly expanded building at 145 Brooklyn Ave. on Sept. 20 and 21 and became one of the world's newest and oldest children's museums. The newly expanded museum, founded in 1899, is also slated to be one of the first museums in the city to "go green" and receive certification from the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) program. Among the facility's green features are flooring and display cases made from renewable or recycled content, a geothermal heating and cooling system, photovoltaic panels to generate electricity, and waterless urinals. World-renowned architect Rafael Viñoly designed the expansion of the museum. This expansion doubles the museum's space, along with its new exhibitions and collections of 30,000 natural-history specimens and cultural artifacts. Viñoly created a two-story design that wraps and incorporates the museum's former building. The 51,000 s/f expansion adds to the museum's existing 51,000 s/f for a new combined total of 102,000 s/f. In planning the expansion and developing its Capital Master Plan, the museum worked closely with community leaders, city partners, and national advisors. The project has raised a total of $80 million over 10 years for the expansion of its facility, exhibits, programs, and endowment. The city provided a total of $48 million for the expansion and renovation of the building, with an additional $1 million coming from NYS, totaling $49 million. The museum raised $19.5 million from private sources and competitive government grants for new exhibits, programs, and endowment, with a further $11.5 million raised toward future phases of the master plan.