Now students take the facts from Phase 1 and relate them: mapping the costs and benefits of expansion, questioning real primary sources, and building an argument from evidence. Deep learning is where knowledge becomes usable — the bridge to the problem.
Build a class concept map with "How far should the nation expand — and at what cost?" in the center. Put westward expansion as the cause, then draw arrows to its effects. Sort each effect as an opportunity, a conflict, a displacement, or a step toward sectional crisis — the same event can be more than one.
| Effect of expansion | An opportunity for… | A cost for… |
|---|---|---|
| New land opens for settlement | settler families seeking farms and a fresh start | Native nations whose homelands were taken |
| The U.S. gains the Southwest & California | the growing nation's economy and ports | Mexican residents who became foreigners on their own land |
| Each new territory reopens slavery | the South, seeking new slave states; the North, seeking free ones | the union — expansion hardened North vs. South into sectionalism |
Talk move: draw an arrow from any effect to the region whose economy it shaped (North's free labor, South's slave labor, the West's farms) and say the sentence aloud. This rehearses §113.20(c)(12).
Give pairs two short, district-approved excerpts that disagree — for example a passage voicing Manifest Destiny (the U.S. is destined to expand across the continent) and a contrasting viewpoint (a critic of the war with Mexico, or a Native or Mexican perspective on losing homelands). Use a four-question source routine:
Credibility & frame check (c)(29)(B): is this a booster of expansion, a critic of it, or an official record? Whose experience is missing from the source, and how can we tell?
📚 Primary sources & analysis tools: DocsTeach · Manifest Destiny documents ↗ · DocsTeach · Treaty of Guadalupe Hidalgo ↗ · National Archives · Treaty of Guadalupe Hidalgo lesson ↗ · LoC · Getting Started with Primary Sources ↗
A low-stakes rehearsal of the reasoning the problem needs. Pose one contested question and have students take a side with evidence, using a claim–evidence–reasoning frame. Then have them steelman the other side — state its strongest point fairly (civil discourse, §113.20(c)(21)).
Sentence stems (ELPS support): "My claim is ______." · "My evidence is ______." · "This matters because ______." · "The strongest point on the other side is ______, and here is why it deserves an answer: ______."
Note: keep this a practice argument about the general question. Weighing whether and how the nation should actually expand — from a stakeholder's point of view — belongs in Phase 3.
Aligned to (not reproduced from) 19 TAC Ch.113 §113.20; effect sizes from Visible Learning MetaX. This scenario dramatizes the real debates over westward expansion in the 1840s.