Grade 3 · Comprehension: Understanding and Responding to Texts · Main Idea and Key Details · Lesson 1

Main Idea and Key Details

The main idea tells what a text is mostly about. Key details explain or support that idea.

The big idea

Ask what all the details have in common

1. Read Think about the whole text, not just one sentence.
2. Notice Find details that repeat, explain, or prove something.
3. State Say the one idea that connects the important details.

Worked example

Which idea fits the whole paragraph?

Leo gathers dry leaves into a pile. He adds fruit peels and vegetable scraps, then turns the pile each week. Months later, the scraps have become rich soil for the garden.

Main idea: Leo turns food and yard scraps into soil by making compost.
Key details: He gathers leaves, adds food scraps, turns the pile, and later gets rich soil. Each detail supports the same main idea.