18
Lesson 18 of 84 · U.S. History
World War I and America
The Industrial Revolution changed manufacturing. Factories replaced workshops, machines replaced hand tools, and cities grew rapidly as people moved from farms to find jobs.
Key Facts
1
Historians use evidence to support claims.
2
Timelines show events in order.
3
Cause and effect explain why things happen.
Check Your Understanding
Question 1
1 of 2Why do we study history?