Geometry: Transformations and Pythagorean Theorem · Weeks 19-27

Rotations

Investigating rotations about the origin (90, 180, 270 degrees) and their effects on figures.

About This Topic

The Mexican-American War focuses on the 1846-1848 conflict that resulted in the United States acquiring the vast 'Mexican Cession', including modern-day California, Nevada, Utah, and Arizona. Students learn about the border dispute in Texas that triggered the war and the intense political debate it caused in the U.S., including opposition from figures like Abraham Lincoln and Henry David Thoreau.

This topic is a major turning point in the road to the Civil War, as the acquisition of new land immediately reignited the battle over the expansion of slavery. The 'Wilmot Proviso' and the Treaty of Guadalupe Hidalgo are key components of the curriculum. Students grasp this concept faster through structured discussion and peer explanation, as they debate the 'justness' of the war and map the massive territorial changes.

Active Learning Ideas

Formal Debate: Was the War Justified?

Divide the class into 'Expansionists' (who believe the U.S. was provoked) and 'Critics' (who believe it was a land grab for slavery). Using primary source quotes from President Polk and Lincoln, they debate the causes of the war.

⏱ 45 min·Whole Class

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Gallery Walk: The Mexican Cession Map

Display maps of the U.S. before and after the war. Students use sticky notes to identify the new states that would be formed and predict how this new land will affect the balance of power between the North and South.

⏱ 25 min·Individual

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Think-Pair-Share: The Wilmot Proviso

Students read about the proposal to ban slavery in any land won from Mexico. They discuss in pairs why this 'proviso' never became law but still managed to outrage the South and unite the North.

⏱ 20 min·Pairs

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Watch Out for These Misconceptions

Common Misconception

The U.S. only fought the war to 'free' the people of the Southwest.

What to Teach Instead

The war was primarily about land and the fulfillment of Manifest Destiny. Peer analysis of President Polk's goals helps students see the strategic and economic motivations behind the conflict.

Common Misconception

Everyone in the U.S. supported the war.

What to Teach Instead

The war was highly controversial, especially in the North, where many saw it as a 'slave-power' conspiracy. A role-play of Thoreau's 'Civil Disobedience' helps students understand the depth of the anti-war sentiment.

Frequently Asked Questions

What caused the Mexican-American War?

The immediate cause was a border dispute in Texas. The U.S. claimed the Rio Grande as the border, while Mexico claimed the Nueces River. When President Polk sent troops into the disputed area and they were attacked, he asked Congress for a declaration of war, claiming 'American blood has been shed on American soil.'

What were the terms of the Treaty of Guadalupe Hidalgo?

Mexico recognized the Rio Grande as the border of Texas and ceded a vast territory (the Mexican Cession) to the U.S. in exchange for $15 million. This land included all or parts of modern-day California, Nevada, Utah, Arizona, New Mexico, Colorado, and Wyoming.

How did the war lead to the Civil War?

The war added a massive amount of new territory to the U.S., which immediately led to a fierce debate over whether slavery would be allowed in those lands. This 'sectional' conflict over the expansion of slavery broke the political compromises of the past and set the nation on a direct path to war.

How can active learning help students understand the Mexican-American War?

Active learning, such as a structured debate on the war's justification, helps students see that history is often a matter of perspective. By mapping the Mexican Cession and discussing the Wilmot Proviso, students connect the military victory to the political crisis that followed. This approach helps them understand that gaining land can sometimes be as destabilizing as losing it.

Browse curriculum by country

• Americas
• US
• CA
• MX
• CL
• CO
• BR

• Europe
• UK
• IE
• FR
• DE
• ES
• IT
• NL
• PT
• SE

• Asia & Pacific
• IN
• SG
• AU