Question

To understand the main idea of an informational text, you should ask yourself

“Does the author include relevant details?”
“What is this mostly about?”

Answer 1

Both questions are useful, but they ask about different things.

- “What is this mostly about?” helps you find the main idea — the central point or the big thing the author wants you to know.
- “Does the author include relevant details?” checks whether the supporting details actually help explain or prove the main idea (and helps you distinguish important details from examples or trivia).

Quick checklist to find the main idea
1. Ask: Who or what is the text about? What is the author saying about it? Try to put that in one sentence.
2. Read the title, headings, first and last paragraphs — authors often put the main idea there.
3. Look for repeated words, phrases, or ideas.
4. Identify supporting details that explain, define, or give reasons/examples for the main idea.
5. Ignore side notes, small examples, or extra facts that don’t support the main point.

Short example
Text: “Polar bears live on Arctic sea ice and hunt seals there. As the ice melts from warming, bears have less hunting ground and struggle to find food. Scientists warn that fewer seals and longer swims are harming polar bear populations.”
Main idea (one sentence): Climate change is reducing Arctic sea ice and threatening polar bears’ ability to hunt and survive.
Relevant details: melting ice, less hunting ground, fewer seals, longer swims — these support the main idea.

Use “What is this mostly about?” to state the main idea and “Does the author include relevant details?” to check that the details support that main idea.