Choosing Which Words to Teach Before the Volcano Text
Ms. Liu's third graders will read a three-page science text on volcanoes. She has flagged 12 words: lava, magma, erupt, vent, crater, crust, mantle, pressure, beneath, surface, ash, fertile. Eight of her 26 students are English learners, five at intermediate proficiency; six students read below grade level. The unit test requires students to explain how magma becomes lava. She has 30 minutes for vocabulary before reading and plans to pre-teach all 12 words with student-friendly definitions and example sentences. Her coach suggests teaching five words well and letting the text do more of the work.
1. Which words should Ms. Liu prioritize, and by what criteria? Explain why teaching all 12 before reading is not the best use of the 30 minutes.
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Prioritize words that are (a) essential to the unit's core explanation, (b) unlikely to be learned from context or the diagram, and (c) generative beyond this text.
A strong five would be magma, lava, erupt, pressure, and beneath. Magma and lava are central to the required explanation and the text's diagrams help, but the contrast must be taught explicitly. Erupt is morphologically generative (eruption, erupted, erupting). Pressure and beneath are general academic words that appear across content areas and may not be inferable for English learners.
The remaining words can be handled more efficiently: vent, crater, crust, mantle, and ash can be labeled on a diagram with brief glosses; surface and fertile can be addressed during reading or in a post-reading semantic map. Pre-teaching all 12 in one block creates cognitive overload, uses time on words the text supports, and reduces rehearsal for the words that carry the unit's core concept.
2. How should Ms. Liu support the English learners and below-grade-level readers during the five-word pre-teach?
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Use multimodal, interactive supports rather than longer definitions:
- Visuals and gestures: a cross-section diagram for magma/lava, a pressure demonstration, and a physical gesture for beneath.
- Cognate and morphology support: point out Spanish cognates such as magma, lava, and presión; build the erupt/eruption/erupting family.
- Student-friendly definitions plus examples and non-examples: 'Pressure is force pushing on something-like squeezing a balloon.'
- Structured oral practice: partner talk with a sentence frame ('Magma is ______; lava is ______ because ______').
- Brief native-language glossary for the five priority words, not a full translation of the text.
Keep the pre-teach to about 15–20 minutes and reserve time for students to encounter the words in the text.
3. What should happen during and after reading for the words she did not pre-teach?
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During reading, teach students to use the available supports: diagram labels, boldface words, and context. Model one context-clue think-aloud with a remaining word, then have students mark words they cannot resolve. Stop only for words that block understanding of the core explanation.
After reading, consolidate with a concept map linking magma → pressure → vent/eruption → lava, with students adding the remaining terms to the map. Then have students orally explain how magma becomes lava using at least three target words. This keeps vocabulary instruction tied to the content explanation rather than turning it into a list-memorization task.