Central Ideas & Details — Core Skills

Central Ideas: The Basics

Part 1 of 2 — One Skill, One Idea

Two question types show up over and over on the reading section:

• Central idea — "What is this whole paragraph about?"
• Detail — "What does the passage say about one specific thing?"

They sound similar, but they ask for opposite-sized answers. Knowing which one you are on is most of the work.

Central idea = the roof over every sentence

The central idea has to cover the whole paragraph, not one sentence of it. Picture a roof: it has to sit over every room in the house.

A very common wrong answer is a sentence that is true but too small — it covers one room. If a choice only matches one line of the passage, it is a detail, not the central idea.

Detail = go find the exact line

For a detail question, the answer is written in the passage. You are not deciding anything. You are locating a line. Wrong choices for detail questions are usually true in real life but never appear in the text.

Worked example

Honeybees share the location of food using a "waggle dance." How long the bee waggles tells other bees how far away the food is. The angle of the dance tells them which direction to fly. Other bees watch, then fly straight to the food.

Central idea? Every sentence is about bees using a dance to tell other bees where food is. So: honeybees use a dance to communicate the location of food. That is the roof.

Detail: what does the length of the waggle tell other bees? Go find the line. Sentence two: distance. Done — no thinking required beyond locating it.

Notice that "the angle tells them direction" is true, but as a central idea it is too small. It covers one room.

Central Ideas: Practice

Part 2 of 2 — Run the Steps

The steps

1. Read the question first. Find out whether it wants the big point or one specific fact before you read the passage.
2. Read the passage once, normally. These paragraphs are short. One careful pass is enough.
3. If it is a central idea question, say the point in your own words in one short sentence before looking at the choices.
4. If it is a detail question, go back and put your finger on the line. The answer is in the text.
5. Test each choice against the passage. A choice must be supported by the words on the page — not by what you already know about the topic.

Where the main idea usually hides

Most short passages announce the point in the first sentence or the last sentence. The middle is usually examples and support. That is not a rule you can lean on blindly, but it is a good place to start looking.

The three wrong-answer shapes

• Too small — true, but it only covers one sentence. Common on central idea questions.
• Not in the text — sounds reasonable, maybe even true in real life, but the passage never says it.
• Backwards — takes something the passage says and flips it.

One rule that saves points

Answer only from the passage. If you know a lot about sharks and the passage says something different about sharks, the passage wins.