Teaching children in their preferred learning style could improve learning outcomes. This approach is commonly justified in terms of brain function, despite educational and scientific evidence demonstrating that the learning style approach is not helpful.
This website gives some sample pages from the book, 50 Debate Prompts for Kids. I liked this because the book first teaches the basic guidelines and reasoning for debates, then equips the teacher with potential topics and how to teach them. This would be useful in any grade classroom because you can adapt the ideas for the different levels, but the objectives for debates stay the same.
Should every US high school student have to pass a citizenry exam? An interesting debate is brewing over how informed our students need to be about state and local government: http://www.governing.com/topics/education/gov-arizona-civics-test-north-dakota-oregon.html