Use this challenge as a fun writing activity that asks you tough questions about community. In the end, you might even have a really engaging discussion about what a "perfect" community really is.
Think about the town, country, and world you live in now. What are the flaws of these communities?
Create the "perfect" society. What would the government be like? Economy? Education? Functionality? Write about a world you think would be perfect to live in.
After you write, show your friends your perfect world. Discuss with them whether or not it would be better to live in your perfect world, or a flawed world. Look at the worlds they created too.
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