Draw evidence from informational texts to support analysis, reflection, and research.
Common Core State Standards, Grades 9-10, Writing: History, Science & Technical Subjects · Read it at the source · Checked October 14, 2026
What WHST.9-10.9 Means in Plain English
Ninth and tenth graders build history and science writing on evidence from what they read: primary sources, data sets, agency reports and technical readings. A biology student explaining why a street’s ash trees died quotes the bulletin’s account of the beetle and the city’s survey numbers, and connects them.
WHST.6-8.9 and WHST.11-12.9 use the same words, so the growth is in the texts: grades 9 to 10 draw on denser reports and data sets than grades 6 to 8, and grades 11 to 12 pull from longer, more technical sources.
WHST.9-10.9 I Can Statements
I can choose the evidence that best supports my analysis.
I can quote words and cite numbers from a reading precisely.
I can explain how each piece of evidence supports my point.
WHST.9-10.9 Worked Example
Both students read the same bulletin and survey; only one built its answer from what the readings say.
Prompt
Biology. The 40 ash trees on Linden Avenue went from healthy to dead in about three years. Using the two readings, write a paragraph that analyzes why the trees died so quickly. Reading 1, a state extension bulletin: the emerald ash borer, a metallic green beetle from Asia, lays its eggs on ash bark; its larvae tunnel through “the layer just under the bark that carries water and nutrients,” and adult beetles leave D-shaped exit holes about 3 millimeters wide when they emerge to lay eggs on other trees. Reading 2, the city forestry department’s survey: in year one, 6 of the 40 trees showed thinning crowns; by year two, 31 had thinning crowns and D-shaped holes; by year three, 37 were dead or dying, and bark peeled from them showed “winding, S-shaped tunnels packed with sawdust.”
Not YetThe ash trees died because of a bug called the emerald ash borer. Bugs like this are really bad for trees, and the city should have done something sooner. It is sad that all the trees are gone.It names the cause but draws no evidence from either reading: no tunnels, no exit holes, no numbers from the survey. The second and third sentences trade analysis for opinion and feeling, so the paragraph never explains why the trees died so quickly, which is the question.
Meets the StandardThe Linden Avenue ash trees died quickly because emerald ash borer larvae destroyed the tissue each tree needed to move water and nutrients. According to the extension bulletin, the larvae tunnel through “the layer just under the bark that carries water and nutrients,” and the city’s survey found exactly that damage: bark peeled from the dying trees showed “winding, S-shaped tunnels packed with sawdust.” A tree whose supply layer is cut in many places cannot feed its highest branches, which explains why thinning crowns were the first sign the survey recorded. The survey’s numbers also show how fast the beetles spread, from 6 trees with thinning crowns in year one to 31 with thinning crowns and D-shaped exit holes in year two. Because each exit hole marks an adult beetle leaving to lay eggs on another tree, every infested ash spread the infestation further, which is why 37 of the 40 trees were dead or dying by year three.Every claim rests on evidence drawn from the readings: the bulletin explains the mechanism, the survey supplies the observations and the counts, and the writer quotes exact wording where it matters. The analysis lives in the connecting sentences, which explain why cut tunnels thin a crown and why exit holes speed the spread, so the evidence answers “why so quickly,” not just “what.”
Moves to Use
Answer the question in the first sentence, then prove it from the readings.Pair a mechanism from one text with observations from another.Quote exact words for key details and cite numbers precisely.Follow each piece of evidence with a sentence explaining what it shows.
Common Mistakes with WHST.9-10.9
Analysis with no evidence
“Bugs like this are really bad for trees.”
Try this: Require every analytical sentence to point to a specific detail, quotation or number from one of the readings.
Quotations left to speak for themselves
Two long quotations in a row with no sentence explaining either one
Try this: Teach a pairing rule: every quotation or number is followed by one sentence explaining what it shows about the question.
Answering a different question
A paragraph on what the city should have done, when the prompt asked why the trees died
Try this: Have students underline the question word in the prompt, such as why or how, and check that their claim answers it.
Which reading supplies the mechanism and which supplies the observations?
The extension bulletin explains how the larvae tunnel under the bark; the city survey records the thinning crowns, exit holes, S-shaped tunnels and counts of affected trees.
How does the strong response explain the speed of the die-off?
Each D-shaped exit hole marks an adult beetle leaving to lay eggs on another tree, so infested trees spread the infestation, from 6 trees in year one to 37 dead or dying by year three.
Why does the weak response fall short of WHST.9-10.9?
It draws no evidence from either reading, and its last two sentences give an opinion and a feeling instead of analysis.