P.S. 186 on 145th Street between Broadway and Amsterdam in Harlem has not echoed with the thud of books or the hum of adolescent gossip since the mid-1970’s. Its “green roof” would be enviable if it weren’t for the fact that lush green leaves are the only things between the sky and the inside of much of the top floor. Trees have taken root in the abandoned building and their branches and foliage peek out of glassless windows and formerly stately arches.Now, the M.L. Wilson Boys and Girls Club has plans for the graffiti-strewn building—plans that include demolition. But not everyone in the community is on board with that idea. The club is planning a development that includes a large Boys and Girls Club facility, a school, 90 units of affordable housing and a commercial space which might be a U.S. post office.