Parents and activists were among the Nebraska citizens appealing to state education leaders to preserve elements of the state's proposed social studies standards during a statewide public hearing recently. Among the two most talked-about subjects were "American exceptionalism" and aspects of geography that relate to human impact on the natural world, such as deforestation and climate change. The state Education Department will take public comments until Nov. 28, and the state Board of Education plans to review a final draft of the standards at a Dec. 7 meeting.