Issues that have been contentious in public about the future of schools in the District seem poised to disappear behind closed doors—including where to put new schools, better sharing of good ideas, reducing student mobility, serving those students not now thriving, and getting better information to families puzzled by the dizzy array of choices. These and more will be on the agenda for a new “Cross-Sector Collaboration Task Force,” according to materials released August 19 by Deputy Mayor for Education, Jennifer Niles.