Common Core LiteracyGrades 9–10Science & Technical

RST.9-10.9: Comparing Findings Across Sources

Also written as CCSS.ELA-LITERACY.RST.9-10.9 · Cluster: Integration of Knowledge and Ideas.

The Official Wording

Compare and contrast findings presented in a text to those from other sources (including their own experiments), noting when the findings support or contradict previous explanations or accounts.

Common Core State Standards, Grades 9-10, Reading: Science & Technical Subjects · Read it at the source · Checked October 14, 2026

What RST.9-10.9 Means in Plain English

Ninth and tenth graders set a text’s findings beside other sources, including their own lab results, and note where they confirm or contradict earlier explanations. A class test of the five-second rule agrees with a published study about wet food but overreaches about dry food.

In grades 6 to 8 (RST.6-8.9), students compared what experiments, simulations or video showed with what a text said. Ninth and tenth grade compare the findings, noting support and contradiction. In grades 11 and 12 (RST.11-12.9), students synthesize many sources into one account, resolving conflicts when possible.

RST.9-10.9 I Can Statements

I can find where two sources report the same finding.
I can spot a conclusion that goes further than its data.
I can say whether a finding supports or contradicts another source.

RST.9-10.9 Worked Example

A class lab on the five-second rule meets a published study, and the weak answer calls them a match where they actually split.

Read the Story

Class lab report: Does the five-second rule hold? We coated a square of floor tile with a harmless bacterium, dropped cubes of watermelon and gummy candy on it, and picked them up after 1 second or 5 seconds. Each piece was pressed onto an agar plate, and colonies were counted two days later.Results: watermelon picked up colonies at both times, about 40 after 1 second and 70 after 5. Gummy candy picked up 3 or fewer at both times. Our conclusion: wet food is never safe to eat off the floor, and dry food is safe if picked up quickly.Second source: in a 2016 Rutgers University study, researchers tested four foods on four surfaces at contact times from under 1 second to 5 minutes. They found that bacteria began transferring in under 1 second, that longer contact usually transferred more, that watermelon picked up the most and gummy candy the least, and that carpet transferred less than tile or stainless steel.

A short passage written for this page.

Question: Where do the class findings support the Rutgers study, and where does the class go beyond it or contradict it?

Not Yet“Both sources agree that the five-second rule is true for gummy candy and false for watermelon, so the class lab proved the study right.”The study never says the rule is true for any food: it found transfer in under a second. The answer also skips the class’s own conclusion that dry food is “safe,” which their colony counts do not show and the study contradicts.

Meets the Standard“The class findings support the study on moisture: both found watermelon picked up far more bacteria than gummy candy, and the class’s jump from about 40 to 70 colonies matches the study’s finding that longer contact usually transferred more. But the class conclusion goes beyond its data. ‘Dry food is safe if picked up quickly’ conflicts with the study’s finding that ‘bacteria began transferring in under 1 second,’ and the class’s own gummy candy still picked up as many as 3 colonies, which is fewer, not none. The class also tested only tile and two times, so it cannot speak to carpet, where the study found less transfer.”It separates findings that agree from a conclusion the data does not reach, quotes the study where it contradicts the class, and notes what the class never tested rather than treating silence as agreement.

Question Stems to Use

Which finding appears in both sources? Do they agree?Where does one source’s conclusion go further than its data?Which finding in the second source contradicts the first?What did one source test that the other did not?Does silence in one source count as agreement?

Common Mistakes with RST.9-10.9

Calling any overlap agreement

“Both sources tested watermelon, so they agree.”

Try this: Have students line up the findings side by side and mark each pair as supports, contradicts or not tested in one source.

Comparing conclusions, not findings

Setting “dry food is safe” against the study without checking the class’s own colony counts

Try this: Ask students to compare the numbers each source found before they compare what each source concluded from those numbers.

Treating silence as support

Assuming the class result applies to carpet, which it never tested

Try this: Have students list what each source tested, including surfaces, foods and times, and limit every comparison to conditions both sources share.

Where RST.9-10.9 Fits

Comes BeforeRST.6-8.9Compare what an experiment, simulation or video shows with what a text says on the same topic.

AlongsideWHST.9-10.8Gather information from several authoritative sources and judge how useful each one is.SL.9-10.2Integrate information from several sources and formats, judging the credibility of each.

Comes NextRST.11-12.9Synthesize texts, experiments and simulations into one account, resolving conflicts when possible.

Practice RST.9-10.9

Quick Check

On which findings do the class lab and the Rutgers study agree?
Watermelon picked up far more bacteria than gummy candy, and longer contact usually transferred more.
Which class conclusion does the study contradict?
That dry food is safe if picked up quickly. The study found bacteria began transferring in under 1 second.
What did the study test that the class did not?
Other surfaces, including carpet, which transferred less than tile, and contact times up to 5 minutes.

RST.9-10.9: Other Names

RST.9-10.9CCSS.ELA-LITERACY.RST.9-10.9