Compare the Maya, Aztec, and Inca civilizations across government structure, achievements, and geography.
You have now studied three great civilizations of the Americas, and it is time to set them side by side. The Maya (week 13) were a collection of competing city-states, never one unified empire, known especially for writing, math, and astronomy. The Aztec (week 14) built a true empire -- the Triple Alliance -- ruling a huge territory indirectly through conquered cities that paid tribute. The Inca (week 15) built the largest of the three, a tightly centralized empire administered through roads and the quipu across extreme mountain terrain.
Despite real differences, look for what these three civilizations share: all three built monumental architecture (pyramids, temples, terraces) without the wheel used for transportation, and largely without draft animals for pulling loads. Each solved the challenges of its own geography -- the Maya's tropical lowlands, the Aztec's lake island, the Inca's mountains -- with engineering suited exactly to that place. That pattern (different geography, different specific solution, similar underlying ingenuity) is one of the most useful ideas in all of world history.
Mastery looks like: They can compare the Maya, Aztec, and Inca on government structure and signature achievement, and explain the shared pattern of geography-specific engineering.
Common stumbles: Flattening all three civilizations into "similar ancient empires" instead of naming their real structural differences in government.