A developer’s vision for a stunning, hourglass-shaped skyscraper at the corner of 57th Street and Second Avenue is moving forward, albeit in an ill-defined form.  The city’s Educational Construction Fund, which is working with luxury residential developer World-Wide Group on the project, filed plans with the Department of Buildings on Sept. 10 for the project’s first phase: an 11-story building, containing 240,549 square feet for the two public schools...more.