Central Idea
What is a central idea?
The most important point the author is making about a text. It is often not directly stated.
What's the difference between summarizing a text and simply retelling every detail in order?
A summary states only the central idea and the most important supporting details, in your own words, and leaves out personal opinions or minor details.
What makes a piece of evidence 'strong' support for a claim, rather than just an interesting detail?
Strong evidence directly connects to and proves the specific claim being made — not just anything true or interesting about the same general topic.
What's the difference between a fact, an example, and an anecdote?
A fact is a statement that can be proven true. An example is a specific case that illustrates a bigger idea. An anecdote is a brief story about a real event, often used to entertain or make a point.
“The scientist was meticulous, double-checking every measurement three times before recording her results.”
Using context clues, what does meticulous most likely mean?
Extremely careful and precise about details (the clue is ‘double-checking every measurement three times’).
What are the two most common places a central idea is stated or restated in a paragraph or text?
The first sentence (or the title) and the last sentence. Authors often introduce the central idea early and restate it at the end.
“The Riverside Community Garden opened last spring on a vacant lot. Neighbors now grow tomatoes, peppers, and herbs in raised beds. The garden also hosts a Saturday class where kids learn how seeds grow into plants.”
Which is the best one-sentence summary? (A) “The Riverside Community Garden turned a vacant lot into a place where neighbors grow food and kids learn about plants.” (B) “I think community gardens are a wonderful idea for every neighborhood.” (C) “The garden has raised beds.”
A — it captures the central idea and key details without opinion.
B is a personal opinion, and C is only one minor detail, not a summary.
“After a new crosswalk light was installed outside Lincoln Middle School, the number of near-miss accidents reported by crossing guards dropped from 12 in one semester to just 2 the next. The city also repainted the crosswalk lines and added a stop sign the same month.”
Which sentence BEST supports the idea that the new light improved student safety? (A) the city repainted the lines, (B) a stop sign was added, (C) near-misses dropped from 12 to 2, (D) the light was installed outside a school.
(C) — it's the only sentence that directly shows a safety outcome. The others describe related actions but not the result.
“Park ranger Elena Ruiz spent three summers trying to track a shy bobcat that kept avoiding her cameras. One morning, she found the bobcat resting just ten feet from her tent, unbothered by her presence for the first time.”
Why would an author most likely include this anecdote in an article about wildlife researchers building trust with animals?
To help readers understand, through a real and specific moment, how much patience it takes to earn a wild animal's trust — it makes the bigger idea concrete and memorable instead of abstract.
“Despite the drought, the farmer's stubborn old apple tree still produced an abundant crop this year.”
What does abundant mean in this sentence?
Plentiful; existing in large amounts (a full, large crop despite the drought).
Central idea: “Volunteering benefits both the community and the volunteer.” Detail A: “Some volunteer groups wear matching T-shirts.” Detail B: “Volunteers often say they feel happier after helping others.”
Which detail actually supports the central idea — A or B?
B — it shows a benefit to the volunteer, which the central idea claims. A is true but unrelated; it doesn't support the idea that volunteering benefits anyone.
Passage: “Sea turtles return to the very beach where they hatched to lay their own eggs, sometimes swimming thousands of miles to get there. Scientists believe turtles use Earth's magnetic field like an internal compass to find their way home.” Draft summary: “Sea turtles are amazing creatures that swim home to lay eggs, and scientists think they use Earth's magnetic field to navigate, which is so cool.”
Which part of the draft summary should be cut because it's an opinion, not information from the text?
“...which is so cool” (and arguably “amazing”) — these are the summarizer's personal reactions, not facts from the passage.
“Chef Amara Osei spent two years testing over 200 versions of a sauce recipe before opening her restaurant. Customers now wait up to an hour for a table, and food critics have called her sauce ‘unforgettable.’”
What is true about Chef Osei's approach to her recipe? (A) she got lucky on her first try, (B) she treated it as a long, deliberate process, (C) she copied someone else's recipe.
(B).
“Renewable energy use has grown quickly worldwide. In 2010, solar and wind made up less than 2% of global electricity. By 2023, that number had risen to nearly 15%. Countries like Denmark now get more than half their electricity from wind alone.”
How does the author illustrate the idea that renewable energy use is growing? (A) by listing examples and numbers, (B) by telling a personal story, (C) by comparing two unrelated topics, (D) by stating an opinion.
(A) — the author uses statistics and a country example (Denmark) to illustrate the growth, rather than narrative or opinion.
“After the accident, the once-fearless skater felt hesitant to try the same jump again.”
What does hesitant mean here, and what context clue tells you?
Reluctant or unsure; the clue is the contrast with ‘once-fearless’ — something changed from confident to unsure.
Which detail does NOT support the central idea?
Central idea: “Getting enough sleep helps the brain store new memories.”
A: “Students who slept well after studying scored higher on a test the next day.”
B: “Many teenagers stay up late finishing homework.”
C: “Brain scans show more activity in memory-related areas during deep sleep.”
B — it's a true fact about teenage habits, but it doesn't show sleep helping (or hurting) memory. A and C both connect sleep to memory directly.
“Wind turbines convert moving air into electricity. A single large turbine can power about 1,500 homes. Turbine blades can also pose a risk to birds and bats, so companies now use radar systems to briefly pause turbines when large flocks approach.”
Which one-sentence summary captures the WHOLE passage rather than just one part of it? (A) “Wind turbines can pose a risk to birds and bats.” (B) “Wind turbines generate electricity, and companies are working to reduce the risk they pose to wildlife.” (C) “A single turbine can power 1,500 homes.”
B — it covers both ideas in the passage (power generation AND the wildlife-safety effort).
A and C each summarize only one detail.
“A local library extended its hours to include Sunday afternoons. In the first three months, Sunday visits averaged 340 people, more than any other single day. The library also added a new children's reading nook and a 3D printer during the same renovation.”
Select TWO pieces of evidence that support the idea that extending hours to Sunday was popular. (A) ‘extended its hours to include Sunday afternoons,’ (B) ‘Sunday visits averaged 340 people,’ (C) ‘more than any other single day,’ (D) ‘added a new children's reading nook,’ (E) ‘added a 3D printer.’
(B) and (C) — both directly show high, comparatively strong Sunday attendance.
(A) just states the change was made; (D) and (E) describe unrelated renovations.
1. “Firefighters in the U.S. respond to over 1 million structure fires a year.”
2. “Smoke detectors cut the risk of dying in a home fire by more than half."
3. “One firefighter, Marcus Webb, credits a single working smoke detector for giving his family the 90 seconds they needed to escape a kitchen fire in 2019.”
Which of the three labeled sentences is the anecdote, and how can you tell?
The Marcus Webb sentence — it tells a brief story about one specific real person and event, rather than stating a provable fact or a general example.
“The museum's oldest manuscripts are so fragile that visitors may only view them through glass, never touching the pages.”
What does fragile mean in this sentence?
Easily damaged or broken; the clue is that visitors can't touch the pages and must view them through glass.
“Monarch butterflies travel up to 3,000 miles each fall, flying from Canada to central Mexico. No single butterfly makes the whole round trip — it takes three or four generations to complete the journey. Scientists still aren't entirely sure how butterflies that have never made the trip before know which way to fly.”
State the central idea of this passage in your own words, and give one supporting detail.
Central idea (accept reasonable paraphrase): Monarch migration is a remarkable, still partly mysterious journey spanning several generations. Supporting detail (any one): The 3,000-mile distance, that it takes 3-4 generations, or that scientists don't fully understand the navigation.
Karen is in a hurry because...
Screech! Karen stomped on the gas pedal the moment the light turned green. She looked over her left shoulder and zigged past a semi-truck. She zoomed ahead and looked over her right shoulder and then zagged past a motorbike. She glanced at the clock on the console and darted into the parking lot. Whipping into a parking spot, she grabbed her suitcase and ran through the lot, up the escalator, and into the terminal. Her heavy suitcase was bumping and bouncing the whole way. Just as she entered the terminal, she heard an announcement over the loudspeaker, "Final boarding call for flight 205 to JFK..." Karen looked at her ticket and then at the line to get through the security checkpoint, which wrapped around several turnstiles and slithered like a lethargic snake. Karen sighed and then slowly walked to the customer service desk.
What is...Karen is in a hurry because she is trying to catch a flight.
“A neighborhood watch group started weekly evening walks through the park two years ago. Since then, reported vandalism in the park has fallen by 70%. The parks department also installed brighter lighting near the playground last year.”
Someone claims the watch walks are the main reason vandalism dropped. Cite one piece of evidence that supports this claim, and explain one reason the claim still might not be fully proven.
Evidence: vandalism fell 70% since the walks started. Explanation: the brighter lighting installed last year could also be a cause, so the walks alone can't be proven as the single reason — the two changes overlap in time.
“Community murals have become a popular way for neighborhoods to reduce graffiti and build local pride. Studies show that walls painted with murals are vandalized far less often than blank walls. In Philadelphia, one mural program transformed over 4,000 walls citywide. Muralist Dana Cole recalls how a single mural on her old school got the whole block talking to each other for the first time in years.”
Explain how the facts, example, and anecdote in this passage work together to develop its key idea.
The fact (murals reduce vandalism) establishes a provable benefit; the example (Philadelphia's 4,000 walls) shows it happening at scale; the anecdote (Dana Cole's story) makes the abstract benefit — community connection — feel personal and real. Together they build the idea that murals do more than decorate; they change how a neighborhood functions.
“The two rival companies decided to collaborate on the new bridge design instead of competing separately, combining their engineers into one team.”
What does collaborate mean, and what in the sentence proves it?
To work together; the clue is ‘combining their engineers into one team’ instead of competing separately.