If you want to be a strong reader, you need to master a key skill: identifying main ideas and supporting details. But before we dive into how to find them, we need to answer a common question: what is the difference between the topic and the main idea?
Simply put, the topic is the general subject a paragraph is about. The main idea, on the other hand, is the specific point the writer is making about that topic.
Usually, you can figure out the main idea by looking at the paragraph’s topic sentence. Let’s look at a brief example:
“Cell phones today come equipped with HD cameras.”
In this sentence, cell phones is the topic. The phrase come equipped with HD cameras tells us what the writer will say about the topic. This is also called the controlling idea.
Together, the topic and the controlling idea create the topic sentence, which gives us a clear understanding of the main idea.
Finding the Main Idea in Real Life
Let’s look at a more relatable example. Imagine your friend sends you this text message:
“If you’re not busy tonight, can we study together in the library? I need more time preparing for the test next week. Algebra is difficult this year.”
In this message, what’s the actual point your friend is trying to make?
- Is the point that algebra is difficult?
- Is the point that they need more time to prepare for the test?
- Or is the point that they want to study together tonight?
Ultimately, their main point is that they want to study together in the library tonight. After making this point, your friend supports it with two reasons: they need more time, and algebra is difficult. These reasons are the supporting details.
A helpful way to understand this relationship is to picture an umbrella. Think of the main idea as a large umbrella that covers and connects all the other information (the supporting details) underneath it.
Putting It to the Test
Let’s look at one final example. Here is a short paragraph about the famous educator Jaime Escalante:
“Escalante’s classroom challenges and successes were the topic of much public discussion in 1988. That year his story was the subject of a book entitled Jaime Escalante: The Best Teacher in America and a film called Stand and Deliver starring James Edward Olmos. Both educators and students have found Escalante’s work at Garfield inspiring.”
In this paragraph, what is the main idea? Consider these four statements:
- Escalante’s classroom became a much-discussed subject.
- A book was written about Escalante.
- A film was produced about his experiences.
- Students and educators were inspired by what he did.
Which one is the general statement, and which ones are just specific details?
If we look closely, we can see that options 2, 3, and 4 are just specific examples supporting option 1. Therefore, we can confidently say that “Escalante’s classroom became a much-discussed subject” is our topic sentence and the main idea of the text.