AP U.S. History / Period 1: 1491–1607
Lesson
European contact
The Columbian Exchange transformed multiple continents.
Explanation
European exploration brought new goods, diseases, animals, crops, and political conflicts. The Columbian Exchange transformed societies on multiple continents.
Practice
Original Marlow Works items. Check the answer explanation after you try.
Which weakness of the Articles of Confederation most directly encouraged support for a new constitution in the 1780s?
Original Marlow Works item — not a College Board question.
Take your time—this is practice, not a test.
Related resources
External links with reuse status. Marlow Works is independent and does not copy restricted exam or textbook material.
Official / link only
AP U.S. History course page
Official nine-period framework, skills, and exam updates.
College Board · All rights reserved · accessed 2026-10-01
Open sourceCC BY — attribution required
U.S. History (Open Textbook Library)
Open U.S. history textbook for chronology and institutions background.
Open Textbook Library listing · CC BY · accessed 2026-10-01
Open source