03/22 Main Idea

The main idea of a story or passage is what the passage is mostly about. It is the basic idea that the author wants the reader to understand.

Sentences that help to support, or explain, the main idea are called supporting details.

Why did the author write this passage? What is the passage mostly about?

Do all of the sentences in the passage support this idea?

If the answer to this question is yes, then you have found the main idea! Let's try these steps to find the main idea in the story below:

During the War of 1812, the British set fire to the U.S. Capitol. They also burned the 3,000 books in the Library of Congress. Thomas Jefferson helped create the library when he was president. He chose books. He hired the first two librarians. When the war started, he was retired. He had a library of books at his home. It was known as the finest private library in the country.

He offered to sell Congress his 6,487 books for $23,950. He hoped to build a new Library of Congress. Congress was excited to get the books for such a low price. His books were about many things. The library once had books about only money, history, and law. Jefferson's books were about art, science, and more. He also had books in French, Spanish, and Latin. He thought Congress should read about all subjects.

The main idea is that Thomas Jefferson helped rebuild the Library of Congress after the War of 1812. The other sentences in the passage support this idea. For example, the first paragraph explains why the Library of Congress needed rebuilding. The second paragraph explains how Jefferson helped rebuild the Library of Congress. He did this by selling the government his books for a low price.