Write informative/explanatory texts, including the narration of historical events, scientific procedures/ experiments, or technical processes.
Common Core State Standards, Grades 9-10, Writing: History, Science & Technical Subjects · Read it at the source · Checked October 14, 2026
What WHST.9-10.2 Means in Plain English
Ninth and tenth graders explain an event, an experiment or a technical process, such as how a website stores passwords, to readers who know less. They organize with headings or a table, build extended definitions of key terms, use the field’s precise vocabulary and close on why it matters.
Grades 6 to 8 (WHST.6-8.2) preview what follows, sort information into categories and define terms. Grades 9 to 10 add connections and distinctions, extended definitions pitched to the reader’s knowledge, and discipline norms. Grades 11 to 12 (WHST.11-12.2) build each element on the last and add analogy and metaphor.
WHST.9-10.2 I Can Statements
I can define a key term fully, with what it is and is not.
I can use headings or a table when they help readers.
I can close by explaining why the topic matters.
WHST.9-10.2 Worked Example
Both students explained the same login plan to the same teachers; only one defined its terms well enough for them to approve it.
Prompt
Computer science. Your coding club is building a login page for the science department’s lab-equipment reservation site. Write the section of the design document that explains, for the teachers who will approve the plan, how the site will store passwords. Use a heading, define hashing and salting, and distinguish hashing from encryption. From your notes: a hash function turns any input into a fixed-length string and cannot be run backward; the same input always gives the same hash; a salt is a random string stored with each account and added to the password before hashing; encryption can be reversed by anyone who holds the key.
Not YetPasswords are stored using hashing, which is a way of hiding them. Hashing is like encryption but better. This keeps the passwords safe from hackers.“A way of hiding them” defines nothing a teacher could check, and calling hashing “encryption but better” blurs the one distinction the prompt asks for. There is no heading, salting never appears, and the close announces safety instead of explaining what the plan protects against.
Meets the StandardHow the Site Stores Passwords. The site will never save a teacher’s password itself; it will save a hash of it. A hash function is a calculation that turns any input into a string of fixed length, always the same string for the same input, and it cannot be run backward to recover the input. At login, the site hashes whatever the teacher types and compares the result with the stored hash, so it can confirm a password without ever keeping one. Hashing differs from encryption, which scrambles data so that anyone holding the key can unscramble it: a stolen key would expose every encrypted password, but a hash has no key to steal. The site will also salt each password, adding a random string stored with that account before hashing, so two teachers who chose the same password end up with different hashes. If the reservation database were ever copied, the thief would get salted hashes, not passwords, and would have to guess each account’s password separately, which protects teachers who reuse a password for school email.A heading announces the section, the extended definition of a hash says what it does, what it guarantees and what it cannot do, and the paragraph separates hashing from encryption, the distinction WHST.9-10.2a asks writers to draw. Terms are defined on first use for teachers who are not programmers, and the close states the significance: what a stolen database would and would not expose.
Moves to Use
Open with a heading that names the process the section explains.Build the extended definition: what the term is, what it does and what it is not.Distinguish the term from the idea readers are most likely to confuse it with.Define each technical term on first use, pitched to what the reader knows.End on the significance: what the process protects, prevents or makes possible.
Common Mistakes with WHST.9-10.2
A definition that circles back
“Hashing is a way of hashing passwords so they are hidden.”
Try this: Require every definition to name the category and one property that separates the term from its nearest neighbor.
Formatting as decoration
Six headings for a one-page explanation, or a table that repeats the paragraph word for word
Try this: Ask students to justify each heading or table in one sentence: what does it let a reader find or compare?
Ending on a slogan
“This is why password security is very important in today’s world.”
Try this: Have students end by stating one specific consequence, what happens or is prevented, for the reader named in the prompt.
Rubric GeneratorFree ToolBuild a rubric for technical explanations with rows for definitions, formatting that earns its place, precise vocabulary and the conclusion.InformativeTechnical writingGrades 9-10
Which three parts make up the strong response’s extended definition of a hash function?
What it does (turns any input into a fixed-length string), what it guarantees (the same input always gives the same string) and what it cannot do (be run backward to recover the input).
How does the strong response distinguish hashing from encryption?
Encryption can be undone by anyone holding the key, so a stolen key exposes every password; a hash has no key and cannot be reversed.
Why does the site salt each password before hashing it?
So two teachers who chose the same password get different stored hashes, and a thief who copies the database has to guess each account’s password separately.