The N.A.A.C.P., the nation’s oldest civil rights organization, has struggled in recent years to win over younger African-Americans, who often see the group as out of touch. The N.A.A.C.P.’s board will reinforce that impression if it ratifies an ill-advised resolution — scheduled for a vote this weekend — that calls for a moratorium on expansion of public charter schools, which receive public money but are subject to fewer state regulations than traditional public schools.