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Common Core ELA8th GradeReading: Informational

RI.8.3: Connections and Distinctions in Nonfiction

Also written as CCSS.ELA-LITERACY.RI.8.3 · Cluster: Key Ideas and Details.

All 41 8th Grade ELA Standards

The Official Wording

Analyze how a text makes connections among and distinctions between individuals, ideas, or events (e.g., through comparisons, analogies, or categories).

Common Core State Standards, Grade 8, Reading: Informational Text · Read it at the source · Checked October 14, 2026

What RI.8.3 Means in Plain English

Eighth graders notice the tools a nonfiction writer uses to link ideas or pull them apart: a comparison, an analogy, a set of categories. An article on earthquakes might call one wave a shoved spring and another a flicked rope, and that difference becomes evidence about Earth’s core.

Seventh grade (RI.7.3) looked at how people, events and ideas influence one another. Eighth grade asks how the writer builds those links and contrasts on purpose. In ninth and tenth grade (RI.9-10.3) students analyze how an author orders and connects a whole series of points or events.

RI.8.3 I Can Statements

  • I can find comparisons, analogies and categories in a nonfiction text.
  • I can explain what an analogy shows that plain description would not.
  • I can explain where an author takes a distinction between two ideas.

RI.8.3 Worked Example

The author uses two analogies to separate the waves, then turns the difference into a discovery, and the weak answer misses both moves.

Read the Story
An earthquake sends two main kinds of waves through the inside of the planet, and instruments called seismographs around the world record both.P waves push and pull the rock in the same direction they travel, the way a pulse runs down a stretched spring when you shove one end. They are the fastest seismic waves, so they always arrive first.S waves shake the rock from side to side, like a ripple running along a rope when you flick it. They are slower, and unlike P waves, they cannot pass through liquid, which has no stiffness to carry a sideways shake.That difference let scientists see inside Earth. Stations on the far side of the planet from an earthquake record P waves but no S waves, so something liquid must be blocking them. That is how we know Earth’s outer core is molten metal.
A short passage written for this page.
Question: How does the author use comparisons to tell P waves and S waves apart, and what connection does the author draw from that distinction?
Not Yet“P waves are faster than S waves, so they arrive first. The author also says the outer core is liquid.”Both facts are in the text, but the answer skips the spring and rope analogies that make the difference visible, and it never explains how the difference leads to the liquid core.
Meets the Standard“The author compares P waves to a pulse running down a spring, pushing and pulling, and S waves to a ripple flicked along a rope, shaking side to side. The analogies set up the key distinction: a sideways shake cannot travel through liquid. The author then connects that distinction to a discovery. The far side of the planet gets P waves but no S waves, so something liquid is in the way, and that is the outer core.”It names both analogies and what each shows, states the distinction they prepare, and explains how the author turns that distinction into a conclusion about Earth’s interior.
Question Stems to Use
What two things is the author comparing? How are they alike and different?What does this analogy help you picture that a plain description would not?Where does the author sort things into kinds or categories? Why those?What does the author use this difference to show?How would the text change without the comparison?

Common Mistakes with RI.8.3

Spotting the analogy but not its job

“The author compares P waves to a spring.” and nothing more

Try this: Ask after every analogy, “What does this let you picture?” and have students write the answer in their own words.

Listing differences with no point

A two-column chart of P wave and S wave facts with nothing connecting them to the core

Try this: Add a final row to every comparison chart that asks “So what?” and fill it with the conclusion the author draws.

Stopping at what the two share

“P waves and S waves are basically the same, since both are earthquake waves.”

Try this: Have students finish two sentences for each pair, one starting “Both…” and one starting “But only…”, before they write anything else.

Where RI.8.3 Fits

Comes BeforeRI.7.3Analyze how the people, events and ideas in a text influence one another.
AlongsideW.8.2Organize ideas into broader categories when writing to explain, the same move from the writer’s side.RH.6-8.5Describe whether a history text presents information in sequence, by comparison or by cause.
Comes NextRI.9-10.3Analyze how an author unfolds a series of ideas or events and the connections drawn between them.

Practice RI.8.3

Quick Check

  1. What analogy does the author use for P waves, and what does it show?
  2. What is the key distinction between P waves and S waves?
  3. What connection does the author draw from that distinction?

RI.8.3: Other Names

RI.8.3CCSS.ELA-LITERACY.RI.8.3

Common Core State Standards © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved. Official wording from the Common Core State Standards PDFs at corestandards.org, last checked October 14, 2026. The explanation, I can statements, example, mistakes and practice on this page are EMStudio’s own, written beside the official wording. They are not part of the standard.