Finding the Main Idea
What?
Finding the Central Idea or Issue is a strategy used to find the main idea or issue in the text of
historical and other social studies materials.
Why?
Students need to be able to determine what the central idea or issue is in order to understand
the text they are reading. Identifying the central idea or issue enables them to understand the
essence of the selection they are reading and to recognize both the main idea and its
supporting details.
The central idea or issue in social studies can relate to people, places, things, ideas, events,
dates, culture, or decisions. Answering these four questions can generally identify the main
idea:
• What is the general topic or subject of this selection of text?
• What main idea holds the details together?
• What are some details that support the central idea or issue?
• What is one sentence that states the central issue or summarizes the entire selection?
Sentences: Each sentence has a key idea or issue. To find the main idea of a sentence:
• Ask who or what the sentence is about.
• Ask what the person or object is doing or what is happening to the person or object.
• Separate, from this main idea, the less important details that simply add information
about it.
• Supporting details often tell the reader when, where, why, what kind, and how.
How?
Paragraphs: Most paragraphs have a central idea or issue embedded in the sentences that form
the paragraph. This topic or main idea tells what the paragraph is all about. Often the writer
states the central idea or issue of the paragraph simply and clearly in a topic sentence. To
find the stated main idea:
• Read the paragraph carefully. Ask the questions, “What is the purpose of the
paragraph?” and “What is the general point that the writer is trying to make?”
• Find the words that describe the most important idea of the paragraph. Look for a topic
sentence that states this central idea or issue.
• If the paragraph introduces the topic with a question, look for the answer to that
question in the paragraph. This will be the central idea.
• Write or state the central idea or issue in your own words. Feel free to use words from
different sentences to state or summarize the main idea of a paragraph.
Sometimes the writer does not tell you the central idea or issue directly, but implies or
suggests what the topic is. You need to infer the main idea by thinking about all the sentences
of the paragraph and determining what the sentences are concerned with. To find the implied
central idea or issue of a paragraph:
• Look at all the ideas and details in the paragraph.
• Ask the question, “Do all the ideas and details relate to a single person or event?” If so,
then determine what this topic is.
• Ask the question, “What is the purpose of the paragraph?”
• Use the question “What points are stated most forcefully?” to identify all the key ideas
and details being made about the topic.
• Write a complete sentence that identifies the person or event and tells what the person
is doing or why the event is important.
®SAISD Social Studies Department
Page 1
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Finding the Main Idea
How?
When?
Long Selections: In long selections, the central ideas of individual paragraphs build the
meaning of an entire selection. The main idea of a long selection, or thesis, is the major
point the writer is making throughout the entire selection. To find the central idea or issue of
a long selection:
• Identify the topic of the selection. Skim the selection to identify the general subject.
Look at the title, the headings, and subheadings for clues to the topic. Ask the
question, “What topic do all of the sentences relate to?”
• Decide what the author is saying about this topic. The central idea or issue usually
expresses an opinion or takes a position on a topic. Ask the questions, “What major
point about the topic does the paragraph make?” or “What was the author’s purpose
for writing the work?” to identify the central idea or issue.
• Find the supporting details that add to or clarify the central idea or issue. Ask the
question “What details support the main idea?” to find these details.
• Use the information gathered from the main ideas from the paragraphs to decide on
the most important idea overall. Remember to focus on key points rather than minor
or supporting detail at this point.
• Write in your own words a brief statement that highlights or summarizes the overall
meaning to the selection.
Provide students with opportunities to find the central idea or issue using a variety of written,
visual, and auditory “texts.” Primary and secondary sources, textbook readings, literature,
cartoons and diagrams, graphic information, audio recordings, and video selections are all
appropriate materials for finding the central idea or issue.
Info
Info
Info
Samples
Main Idea
Webbing Diagram
Structural Diagram
®SAISD Social Studies Department
Page 2
Reproduction rights granted only if copyright information remains intact.
Finding the Main Idea
Finding the Central Idea or Issue is a strategy used to find the main idea or issue in the text of
historical and other social studies materials. You need to be able to determine what the
central idea or issue is in order to understand the text you are reading. Identifying the central
idea or issue enables you to understand the essence of the selection you are reading and to
recognize both the main idea and its supporting details.
The central idea or issue in social studies can relate to people, places, things, ideas, events,
dates, culture, or decisions. Answering these four questions can generally identify the main
idea:
• What is the general topic or subject of this selection of text?
• What main idea holds the details together?
• What are some details that support the central idea or issue?
• What is one sentence that states the central issue or summarizes the entire selection?
Sentences: Each sentence has a key idea or issue. To find the main idea of a sentence:
• Ask who or what the sentence is about.
• Ask what the person or object is doing or what is happening to the person or object.
• Separate, from this main idea, the less important details that simply add information
about it.
• Supporting details often tell the reader when, where, why, what kind, and how.
Paragraphs: Most paragraphs have a central idea or issue embedded in the sentences that
form the paragraph. This topic or main idea tells what the paragraph is all about. Often the
writer states the central idea or issue of the paragraph simply and clearly in a topic sentence.
To find the stated main idea:
• Read the paragraph carefully. Ask the questions, "What is the purpose of the
paragraph?"and "What is the general point that the writer is trying to make?"
• Find the words that describe the most important idea of the paragraph. Look for a topic
sentence that states this central idea or issue.
• If the paragraph introduces the topic with a question, look for the answer to that
question in the paragraph. This will be the central idea.
• Write or state the central idea or issue in your own words. Feel free to use words from
different sentences to state or summarize the main idea of a paragraph.
Sometimes the writer does not tell you the central idea or issue directly, but implies or suggests
what the topic is. You need to infer the main idea by thinking about all the sentences of the
paragraph and determining what the sentences are concerned with. To find the implied
central idea or issue of a paragraph:
• Look at all the ideas and details in the paragraph.
• Ask the question, "Do all the ideas and details relate to a single person or event?" If so,
then determine what this topic is.
• Ask the question, "What is the purpose of the paragraph?"
• Use the question "What points are stated most forcefully?" to identify all the key ideas and
details being made about the topic.
• Write a complete sentence that identifies the person or event and tells what the person is
doing or why the event is important.
®SAISD Social Studies Department
Page 3
Reproduction rights granted only if copyright information remains intact.
Finding the Main Idea
Long Selections: In long selections, the central ideas of individual paragraphs build the
meaning of an entire selection. The main idea of a long selection, or thesis, is the major point
the writer is making throughout the entire selection. To find the central idea or issue of a long
selection:
• Identify the topic of the selection. Skim the selection to identify the general subject. Look
at the title, the headings, and subheadings for clues to the topic. Ask the question,
“What topic do all of the sentences relate to?”
• Decide what the author is saying about this topic. The central idea or issue usually
expresses an opinion or takes a position on a topic. Ask the questions, “What major point
about the topic does the paragraph make?” or “What was the author’s purpose for
writing the work?” to identify the central idea or issue.
• Find the supporting details that add to or clarify the central idea or issue. Ask the question
“What details support the main idea?” to find these details.
• Use the information gathered from the main ideas from the paragraphs to decide on the
most important idea overall. Remember to focus on key points rather than minor or
supporting detail at this point.
• Write in your own words a brief statement that highlights or summarizes the overall
meaning to the selection.
You can also use certain clues to find the main idea such as:
• Who: Who is speaking? Who is passing the law? Who is the passage about?
• Wanted: Laws are passed for a reason, what is it? Speakers are speaking for a reason,
what is it? Authors write, what are they saying?
• Why: Why is this law necessary? Is it necessary? Why was this important at the time? Why
is this speech important?
• So...: This is where you tie everything together
Examine the primary document below and be ready to provide the main idea:
Who
Chinese Exclusion Act (1882)
Be it enacted by the Senate and House of Representatives of
the United States of America in Congress assembled, That from
and after the expiration of ninety days next after the passage of
this act, and until the expiration of ten years next after the
passage of this act, the coming of Chinese laborers to the
United States be, and the same is hereby, suspended; and
during such suspension it shall not be lawful for any Chinese
laborer to come, or having so come after the expiration of said
ninety days to remain within the United States.
SEC.10. That every vessel whose master shall knowingly violate
any of the provisions of this act shall be deemed forfeited to the
Why
United States, and shall be liable to seizure and condemnation
in any district of the United States
into which such vessel may
Wanted
enter or in which she may be found.
SEC.15. That the words "Chinese laborers", wherever used in
this act shall be construed to mean both skilled and unskilled
So...and Chinese employed in mining.
laborers
Main Idea:
This law is excluding all Chinese
labor immigrants into the United
States for 10 years.
Main Idea with Historical Context:
This law, banning Chinese laborer
Immigration, was passed in
response to the growing fear on
the west coast of the United States
regarding job competition and
lower wages.
®SAISD Social Studies Department
Page 4
Reproduction rights granted only if copyright information remains intact.