Explain the Great (Connecticut) Compromise and the Three-Fifths Compromise, including how the Constitution's framers dealt honestly and dishonestly with the question of slavery.
At the Constitutional Convention in Philadelphia, the first big fight was about representation. The Virginia Plan, backed by larger states, wanted a Congress based on population -- more people, more votes. The New Jersey Plan, backed by smaller states, wanted every state to have equal votes, just like under the Articles. Roger Sherman and Oliver Ellsworth of Connecticut proposed a solution now called the Great Compromise (or Connecticut Compromise): a two-house Congress, with the House of Representatives based on population and the Senate giving every state exactly two votes, no matter its size. Both sides got part of what they wanted, and Congress has worked this way ever since.
A second, much darker compromise settled how enslaved people would be counted. Southern states wanted enslaved people counted fully for representation in the House (which would give the South more seats and more power), even though those states denied enslaved people any rights at all. Northern states objected. The delegates settled on the Three-Fifths Compromise: each enslaved person would count as three-fifths of a person for both representation and taxation. This gave slaveholding states extra political power in Congress without granting enslaved people a single right -- a compromise that protected slavery's influence rather than confronting it, and a choice whose effects lasted for generations. The delegates also agreed Congress could not ban the international slave trade until 1808 at the earliest.
Mastery looks like: They can explain both the Great Compromise and the Three-Fifths Compromise accurately, including who benefited from each and why.
Common stumbles: Describing the Three-Fifths Compromise vaguely ("about slavery") instead of stating specifically what it counted and why it mattered politically.