Main Idea & Supporting Details
Aligned to RI.4.2 — Common Core State Standards for English Language Arts.
What this lesson teaches
The main idea is the most important point of a passage; supporting details are the facts and examples that back it up. Ask: 'What is this mostly about, and what proves it?'
Worked examples
Example 1
A paragraph listing how bees pollinate crops, make honey, and support ecosystems has the main idea: 'Bees are important to the environment,' supported by those three details.
Example 2
A paragraph on how rivers carved canyons, moved soil, and built deltas has the main idea 'rivers reshape the land,' with those three as details.
Example 3
A detail repeated in every sentence is often the main idea in disguise. Ask what all the sentences have in common.
Practice questions
- Summarize a nonfiction paragraph in one main-idea sentence.
- List two details that support that main idea.
- Why isn't the title always the main idea?
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Idea Principal y Detalles de Apoyo
La idea principal es el punto más importante de un texto; los detalles de apoyo son los datos y ejemplos que la respaldan. Pregúntate: '¿De qué trata principalmente este texto y qué lo demuestra?'
Ejemplo 1: Un párrafo que menciona cómo las abejas polinizan los cultivos, producen miel y sostienen los ecosistemas tiene como idea principal: 'Las abejas son importantes para el medio ambiente', apoyada por esos tres detalles.
Ejemplo 2: Un párrafo sobre cómo los ríos formaron cañones, movieron tierra y construyeron deltas tiene la idea principal 'los ríos transforman el paisaje', con esos tres como detalles.
Ejemplo 3: Un detalle que se repite en cada oración muchas veces es la idea principal disfrazada. Pregúntate qué tienen en común todas las oraciones.
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