Unit 1: Why is Bill Gates richer than my dad? Unit 2. Why are middle class moms and dads going broke? Unit 3. Why do Supreme Court justices live longer than the rest of us? Unit 4: Why does a man's income drop if he has a sex change? Unit 5: Why do black Americans get lower scores on IQ tests than white Americans? Unit 6. Why do good people do bad things? Unit 7. Why are we segregated? Unit 8. Why did footbinding in China persist for centuries and why did it disappear almost overnight? Unit 9. Why didn't soldiers in World War I fight to win? Unit 10. Why do we keep producing carbon emissions and what will it take for us to stop?