The Coin Test
A mentor explainer about the one-second trial inside a vending machine — organized by visible strategies: a definition that names the enemy, a classification into three tests, cause/effect inside each, and a comparison that closes the case. Students map the organizational strategies, then draft their own explainer by CHOOSING a strategy to fit their topic.
Common Core standards covered
- W.7.2Write informative/explanatory texts to examine a topic and convey ideas, concepts, and information through the selection, organization, and analysis of relevant content.
- W.7.10Write routinely over extended time frames (time for research, reflection, and revision) and shorter time frames (a single sitting or a day or two) for a range of discipline-specific tasks, purposes, and audiences.
© Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
Teacher-facing overview
Big idea: Write informative/explanatory texts that examine a topic and convey ideas through the selection, organization, and analysis of relevant content — organizing with strategies such as definition, classification, and cause/effect; write routinely across shorter time frames.
Student target: “I can identify the organizational strategies inside an informative text — definition, classification, cause/effect, comparison, sequence — explain how they nest, and choose the right strategy for my own topic before drafting inside it.”
Success criteria: I can name the mentor's strategies with citations, including the nesting. · I can state the choosing rule: the topic's shape votes first. · I can declare my draft's spine strategy before writing sentence one. · I can draft an explainer whose paragraphs each know their organizational job.
Essential question
Every clear explanation is standing on an invisible skeleton — a definition, a classification, a chain of causes. How do you SEE the skeleton in good informative writing, and how do you choose the right one for your own topic?
Learning target: I can identify the organizational strategies inside an informative text — definition, classification, cause/effect, comparison, sequence — explain how they nest, and choose the right strategy for my own topic before drafting inside it.
Success criteria
- I can name the mentor's strategies with citations, including the nesting.
- I can state the choosing rule: the topic's shape votes first.
- I can declare my draft's spine strategy before writing sentence one.
- I can draft an explainer whose paragraphs each know their organizational job.
Why this matters
W.7.2's Grade 7 emphasis is organization BY STRATEGY — the standard names definition, classification, comparison/contrast, and cause/effect as tools students should wield deliberately. Most young writers organize by momentum: they start typing and follow the sentences. This mentor makes strategy visible and NESTED — a definition clearing the ground, a classification providing the spine, cause/effect engines inside each class, comparisons drawing boundaries, all riding a sequence — so students can see that organizational strategies aren't essay formats but thinking shapes, chosen to match the topic's own shape. The choosing rule (the topic votes first) converts 'organize your writing' from a command into a decision procedure, and W.7.10's routine-writing clause gets honored the only way it can be: by drafting today, inside the hour.
Students should already be able to
- Paragraph basics; topic sentences informally.
- The mentor-text habit (reading as a burglar).
- A topic the student can explain without research.
Where this shows up outside the classroom
Assessment plan
Formative — for feedback during the lesson
- Warm-up — strategies surfacing unconsciously, then named.
- Skeleton pass — nesting found, dimensions articulated.
- Draft circulation — declarations matched against drafts.
Summative — the graded evidence: Exit ticket (strategy + declaration + nesting) plus the draft and blind-test result; the full draft and arms-race paragraph rank as extension evidence.
The passage: “The Coin Test — mentor text”
An original explainer written for this lesson (≈600 words). The mechanism — light gates, electromagnetic signatures, timing windows, the deflector — is how real coin validators work.
¶1 Drop a quarter into a vending machine and, in about one second, the machine decides whether to trust you. It cannot see the coin. It cannot ask questions. And yet slugs, washers, foreign coins, and arcade tokens almost never fool it. In that one rattling second, your quarter takes three tests — and it has to pass all three.
¶2 First, a definition, because the machine's enemy has a name: a SLUG is any object shaped to pass as a coin — a punched steel disc, a washer with taped-over holes, a coin from another country worth a fraction of a quarter. Slug-making is as old as coin machines; the first vending machines of the 1880s were beaten within months by cardboard discs. Everything inside a modern coin validator exists because of that arms race.
🔒 The full text — 7 numbered paragraphs, plus the photocopy-ready handout — ships in the kit. See plans →
The task students work on
The class maps the mentor's strategies — the definition (¶2), the three-test classification (¶3–¶5), the cause/effect engines nested inside, the boundary-drawing comparisons (¶4, ¶7), the sequence carrying it all — then learns the strategy menu and its choosing rule: the topic's shape votes first. Every student then declares a topic AND a spine strategy before drafting, and writes the opening plus one body paragraph inside it. Partners check: can you name my strategy from my draft alone?
The strategy map — mentor first, your draft second.
| Strategy | Where the mentor uses it (¶) | What it organizes there | Your draft's use (topic + where) |
|---|---|---|---|
| Definition | |||
| Classification | |||
| Cause/effect | |||
| Comparison | |||
| Sequence |
Anticipated student strategies
Skeleton reading first because strategies must be seen working before they're chosen. The momentum habit interrupted second, at the moment it would start. Topic-shape matching last — the transferable decision procedure.
- Skeleton reading. The student reads the mentor once for content, once naming each paragraph's organizational job.
The intended method — the architecture pass is the lesson. Share first.
🔒 2 more anticipated strategies with select-and-sequence guidance are in the full lesson. See plans →
Lesson script
Collect the approaches and label them live: 'games with rules and winners' — definition; 'there's ball sports, race sports, fight sports' — classification; 'it's like play but organized' — comparison. Name the reveal: everyone chose an organizational strategy in the first five seconds without knowing it. Today we make the choice conscious — because conscious choosers can pick the RIGHT one.
Listen for: Sequence/example — also a strategy, with limits (one story explains an instance, not a category). Every strategy has topics it fits and topics it fails.
The mentor is in the workbook and the handout. Build the strategy map on the board: ¶2 defines (the enemy, before the defense); ¶3–¶5 classify (three tests — and push for the dimensions insight: body, substance, behavior, not arbitrary bins); cause/effect engines nested INSIDE each test (blocked beam → size; wrong signature → no pulse); comparisons drawing boundaries (¶4's fingerprint line, ¶7's economics); sequence carrying everything (the reader rides the coin). Land the nesting principle: strategies aren't rival formats — a real text runs several at once, with one as the SPINE.
- One spine strategy; others nest inside it.
- Good classifications have dimensions, not just bins.
Listen for: Arguably both, married: the classification (three tests) IS sequenced (the coin meets them in order). The best answer: the topic's shape offered both, and the writer took the gift.
🔒 The remaining 4 steps — fully scripted with teacher-says lines, discourse questions, look-fors, and interventions — are in the full lesson. See plans →
Misconceptions and how to respond
- “Organization means intro, three body paragraphs, conclusion.” That's a container, not an organization. The mentor's shape came from its TOPIC — a trial with three tests. Strategies (define, classify, cause/effect, compare, sequence) are thinking shapes; the five-paragraph box is just where some of them happen to fit.
- “Pick one strategy and stick to it.” — the teacher response is in the full lesson.
- “Informative writing ends with a summary of what you said.” — the teacher response is in the full lesson.
- “I'll figure out my organization as I write.” — the teacher response is in the full lesson.
🔒 Every misconception ships with a tested classroom response. See plans →
Scaffolded practice
The workbook follows gradual release rather than a page of blank prompts: 2 fully worked, 2 partially completed, then 4 independent.
- I doLiteral first — the trial. Reconstruct the coin's one-second journey with each test's mechanism, cited.
🔒 7 more prompts across all three release tiers are in the full lesson. See plans →
Worked solutions and scaffolds for every prompt are in the downloadable kit, included with membership. See plans and pricing.
Exit ticket
- One mentor strategy: name, ¶, and its job there.
🔒 2 more exit-ticket questions are in the full lesson. See plans →
Worked answers, the completed answer tables, and the scoring rubric are in the downloadable kit, included with membership. See plans and pricing.
Printable handouts in the kit
All handouts are in Printable_Handouts.pdf inside the kit download.
Materials and classroom resources
Student experience
Students enter through a low-floor prompt, build or sketch a model, test a strategy, revise their thinking, collaborate, and present a final solution. The task remains accessible while allowing for sophisticated reasoning.
Detailed facilitation notes
- Step 1: Read the mentor; feel the one-second trial happen in order. Ask: “What do you notice?”, “What could you try next?”, and “How can you prove that?”
- Step 2: Map the strategies: where it defines, where it classifies, where it runs cause/effect. Ask: “What do you notice?”, “What could you try next?”, and “How can you prove that?”
- Step 3: Learn the strategy menu — and how the mentor picked from it. Ask: “What do you notice?”, “What could you try next?”, and “How can you prove that?”
- Step 4: Draft your own explainer: choose your strategy FIRST, then write inside it. Ask: “What do you notice?”, “What could you try next?”, and “How can you prove that?”
Differentiation and inclusion
Support: The strategy menu turns 'organize your writing' into a concrete choice; extend with the strategy-swap rewrite and the arms-race ending analysis.
Language support: “I started by…”, “My model shows…”, and “I know my answer is reasonable because…”.
Extension: Require a second solution, alter a condition, or have students write a challenge for another group.
Accessibility: Manipulatives, enlarged visuals, oral response choices, partner reading, and reduced-copy student pages.
Assessment plan
Formative checks: Strategy choice, accuracy, representation, collaboration, and explanation.
End evidence: One strategy identification in the mentor (named, cited) plus a drafted explainer opening with its chosen strategy declared and begun.
Mastery: The student completes the task accurately and explains the strategy with limited prompting.