Overview

Lesson Procedure

60-65 minutes of class time across 5 phases.

1. Warm-Up5 minutes
2. Direct Instruction15-20 minutes
3. Guided Practice15 minutes
4. Independent Practice20 minutes
5. Closure5 minutes

1. Warm-Up5 minutes

   Project this label from an invented cereal box: "Studies link a good breakfast to better focus in class. Start every school day with Crunch-O's!"

   Warm-Up Prompt

   What does the label want you to do? What evidence does it give, and does that evidence support buying this cereal, or only something more general?

   Take answers. The recommendation is to eat Crunch-O's. The evidence, even if true, is about breakfast in general, so it supports "eat breakfast" but says nothing about this cereal against any other breakfast. The link between the evidence and the recommendation is where the label fails. Tell students that this is today's skill. RST.9-10.8 asks them to assess the extent to which the reasoning and evidence in a science or technical text support the author's claim or a recommendation for solving a problem. The answer is rarely yes or no: it is how far the support reaches.

2. Direct Instruction15-20 minutes

   Part 1: Claim, reasoning, evidence. Post Diagram 1 for the whole lesson. A claim says something is true; a recommendation says what should be done to solve a problem. Evidence is what the author offers as fact: cases, counts, measurements, test results. Reasoning is the "because" that connects the evidence to the claim. To assess support, students ask four questions (relevant? enough? compared with what? other causes?), then match the strength of the support to the exact words of the claim. Evidence can fully support "in this test" and still fall short of "always."

   Scope words: what each kind of claim needs from its evidence

   If the claim says	The evidence must show	Example of a gap
   may, can, sometimes	at least some real cases, clearly described	The cases are hearsay, with no source
   often, frequently, usually	many cases, from more than one place or observer	One striking case is offered as the pattern
   always, never, every	no exceptions, over a wide range of conditions	One test under one set of conditions
   causes, prevents, reduces	a fair comparison in which the one factor is the main difference	The two groups also differ in another way

   Part 2: Model with Holmes (T1). In 1843 the Boston physician Oliver Wendell Holmes told his colleagues that doctors and nurses were carrying a deadly disease to women in childbirth. Puerperal fever ("childbed fever") is an infection of the womb after giving birth; in the nineteenth century it killed many new mothers. Holmes did not know what caused it; bacteria were not yet understood. He built his case from reports of other physicians. Gloss before reading: "lying-in" means the weeks after giving birth, "midwifery" is the delivery of babies, and a "charitable institution" here is a charity that paid midwives to deliver poor women. Read T1 aloud once, then work the two examples.

   1The practical point to be illustrated is the following:

   2The disease known as Puerperal Fever is so far contagious as to be frequently carried from patient to patient by physicians and nurses.

   [...]

   3In a letter to be found in the “London Medical Gazette” for January, 1840, Mr. Roberton of Manchester makes the statement which I here give in a somewhat condensed form.

   4A midwife delivered a woman on the 4th of December, 1830, who died soon after with the symptoms of puerperal fever. In one month from this date the same midwife delivered thirty women, residing in different parts of an extensive suburb, of which number sixteen caught the disease and all died. These were the only cases which had occurred for a considerable time in Manchester. The other midwives connected with the same charitable institution as the woman already mentioned are twenty-five in number, and deliver, on an average, ninety women a week, or about three hundred and eighty a month. None of these women had a case of puerperal fever. “Yet all this time this woman was crossing the other midwives in every direction, scores of the patients of the charity being delivered by them in the very same quarters where her cases of fever were happening.”

   5Mr. Roberton remarks, that little more than half the women she delivered during this month took the fever; that on some days all escaped, on others only one or more out of three or four; a circumstance similar to what is seen in other infectious maladies.

   • Pinning down the claim (T1, paragraph 2)

     What exactly does Holmes claim in paragraph 2, and which words set how much evidence he needs?

     Result: The claim is that puerperal fever "is so far contagious as to be frequently carried from patient to patient by physicians and nurses." Two phrases set the scope. "So far contagious" limits the claim: Holmes does not say the disease always spreads this way or that contagion is its only cause. "Frequently" raises the bar: one case would show it can happen, but "frequently" needs many cases from more than one place. So the right test for his evidence is not "Did it ever happen?" but "Does this happen often enough, in enough places, to call it frequent?"

   • Assessing the Manchester numbers (T1, paragraph 4)

     How strong is the evidence in paragraph 4 for the claim? Use the four questions in Diagram 1.

     Result: Relevant: yes; it follows one attendant, the midwife, from patient to patient. Enough: 30 deliveries in one month, 16 cases, and all 16 died; 16 ÷ 30 is about 53 percent, far too many to call a small fluke. Compared: yes, and this is the strength. The other 25 midwives of the same charity delivered about 380 women a month and had no case at all, so the comparison group is large and similar. Other causes: the evidence shows that the cases followed this midwife; it does not show how the disease traveled (her hands, her clothes, the air around her). Judgment: strong support that this midwife carried the disease; partial support for "frequently," because it is one midwife in one town in one month.

   Close the model by naming the two moves. First, pin the claim to its exact words. Second, test each piece of evidence against those words and say how far it reaches. Paragraph 5 adds one more detail about the midwife's cases; students will decide in the quiz what it does for the argument.

3. Guided Practice15 minutes

   Pairs read the facilities memo (T2), a modern technical recommendation written for this page, and label each numbered reason as evidence (measured or stated fact), reasoning, or both. Then work the two examples as a class. A kilowatt-hour (kWh) is the energy used by a 1,000-watt device running for one hour.

   1The problem. The gym is lit by 24 metal-halide fixtures installed 15 years ago. Each one draws 455 watts, counting the ballast that powers the lamp. Four fixtures failed this year. A metal-halide lamp also needs 10-15 minutes to reach full brightness after it is switched on, so staff leave the gym lights on between classes and events. The school and its gym are invented for teaching; the fixture ratings are typical of real products.

   2Our recommendation. Replace all 24 fixtures with LED high-bay fixtures that draw 150 watts each. The installer's quote is $260 per fixture, installed, or $6,240 in all.

   3Reason 1: energy and cost. The gym lights are on about 2,000 hours a year. Each new fixture draws 305 watts less, so the gym would use 24 × 0.305 kW × 2,000 h = 14,640 kWh less electricity a year. At our rate of $0.16 per kWh, that saves $2,342 a year, so the new lights will pay for themselves in about 18 months.

   4Reason 2: light. The sales representative told us the new fixtures will make the gym brighter, and livestreamed games will look better.

   5Reason 3: maintenance. LED fixtures are rated for 50,000 hours, so the school will never have to replace them.

   6Reason 4: switching. LED fixtures reach full brightness the moment they are switched on, so staff can turn the gym lights off whenever the gym is empty. We have not counted these extra savings above.

   • Checking the arithmetic behind a recommendation (T2, paragraphs 2-3)

     Does the memo's own evidence support its claim that the lights "will pay for themselves in about 18 months"?

     Result: The energy figures hold: 455 - 150 = 305 W saved per fixture, and 24 × 0.305 kW × 2,000 h = 14,640 kWh a year. At $0.16 per kWh, that is 14,640 × 0.16 = $2,342.40 a year. The cost is 24 × $260 = $6,240. The payback time is 6,240 ÷ 2,342.40 ≈ 2.66 years, about 32 months, not 18. The evidence supports "the lights will save about $2,340 a year" but not the 18-month figure. Saving the cost in 18 months would need about $4,160 a year. The memo's conclusion goes beyond its own numbers, even though the recommendation may still be a good one.

   • Rating each reason (T2, paragraphs 4-6)

     Rate reasons 2, 3 and 4 as strong, partial or weak support for replacing the fixtures, and say why.

     Result: Reason 2 is weak: its only evidence is what the sales representative said, and the seller gains from the sale; a light-meter reading in foot-candles or lux, before and after a test fixture, would be real evidence. Reason 3 overclaims: a rating of 50,000 hours is about 25 years at 2,000 hours a year (50,000 ÷ 2,000 = 25), and LED ratings usually mean the time until the light output falls to about 70 percent, not the time until the fixture fails, so "never" is not supported. Reason 4 is sound reasoning with no numbers: instant start makes switching off possible, but the memo does not measure how many hours it would save, so it rightly leaves it out of the total.

   Debrief: Should the board reject the memo? Students usually decide no: the main reason, energy, is well supported, and the weak parts can be fixed by correcting the payback figure and replacing the sales claim with a measurement. Assessing support is not the same as rejecting a recommendation; it tells the reader which parts to trust and what to check.

4. Independent Practice20 minutes

   Students read the two texts below on their own and answer quiz questions 1-20. Questions 1-6 and 15 use the Holmes excerpt (T3); questions 7-11, 16 and 17 use the garden memo (T4); question 12 uses Diagram 2, which charts the memo's results; questions 13, 14, 18 and 19 use T1; and question 20 uses T1 and T4 together. T3 comes from the same essay as T1: these are more of the reports Holmes gathered. Tell students before they read: a "practitioner" or "medical man" is a doctor, "delivered" means helped a woman give birth, and "the body ... opened" means an autopsy was done.

   1Dr. Gooch says, “It is not uncommon for the greater number of cases to occur in the practice of one man, whilst the other practitioners of the neighborhood, who are not more skilful or more busy, meet with few or none. A practitioner opened the body of a woman who had died of puerperal fever, and continued to wear the same clothes. A lady whom he delivered a few days afterwards was attacked with and died of a similar disease; two more of his lying-in patients, in rapid succession, met with the same fate; struck by the thought, that he might have carried contagion in his clothes, he instantly changed them, and 'met with no more cases of the kind.' A woman in the country, who was employed as washerwoman and nurse, washed the linen of one who had died of puerperal fever; the next lying-in patient she nursed died of the same disease; a third nursed by her met with the same fate, till the neighborhood, getting afraid of her, ceased to employ her.”

   2In the winter of the year 1824, “Several instances occurred of its prevalence among the patients of particular practitioners, whilst others who were equally busy met with few or none. One instance of this kind was very remarkable. A general practitioner, in large midwifery practice, lost so many patients from puerperal fever, that he determined to deliver no more for some time, but that his partner should attend in his place. This plan was pursued for one month, during which not a case of the disease occurred in their practice. The elder practitioner, being then sufficiently recovered, returned to his practice, but the first patient he attended was attacked by the disease and died. A physician, who met him in consultation soon afterwards, about a case of a different kind, and who knew nothing of his misfortune, asked him whether puerperal fever was at all prevalent in his neighborhood, on which he burst into tears, and related the above circumstances.

   3“Among the cases which I saw this season in consultation, four occurred in one month in the practice of one medical man, and all of them terminated fatally.” [Lond. Med. Gaz. May 2, 1835.]

   1The problem. The district has asked every school to cut its outdoor water use by 30 percent next summer. Our school garden has eight raised beds, each 2 m by 4 m, and all eight are watered with overhead sprinklers. The garden, the test and all data in this memo are invented for teaching.

   2The test. Last summer we kept watering Bed 1 with its sprinkler and fitted Bed 2 with a drip line, a hose with small holes that lets water drip onto the soil at the base of each plant. Both beds grew the same tomato variety, planted on the same day. Each bed had its own water meter, and we watered each bed whenever its soil was dry 5 cm down. Bed 2 is the bed beside the tool shed, which shades it after about 3 p.m. Bed 1 is in full sun all day.

   3Results. Over six weeks in July and August, Bed 1 used 410, 395, 430, 455, 420 and 400 liters, week by week: 2,510 liters in all. Bed 2 used 225, 215, 240, 250, 230 and 220 liters: 1,380 liters in all. Bed 1 gave 18.4 kg of tomatoes and Bed 2 gave 19.1 kg.

   4Our recommendation. Fit all eight beds with drip lines before next summer. Drip used about 45 percent less water, far beyond the district's 30 percent target, and it did not lower the harvest. A drip kit for all eight beds costs $180. The school pays $2.50 for every 1,000 liters of water, and we water for about 14 weeks each summer, so the kit will pay for itself in the first summer. Drip also keeps the leaves dry, so we expect fewer leaf diseases on the tomatoes.

5. Closure5 minutes

   Exit ticket: "Choose one recommendation from today's texts. Write one sentence saying how far its evidence supports it (strongly, partly or weakly), and one sentence naming the single piece of evidence that would most change your rating." Sort the tickets into "judgment tied to the exact claim," "judgment with no reason" and "summary instead of assessment" to plan the next lesson.

   Teacher note on the historical texts. T1, T3 and T5 describe the deaths of mothers after childbirth; prepare students, and let any student who finds the subject difficult work from T2 and T4 for the discussion. The language is of the 1840s: "female" for woman (T5, paragraph 5), "lying-in" for the weeks after birth, "washerwoman" for a woman paid to wash clothes, and "he" for every physician, because the profession then was almost entirely male. Recommendation 8 (T5, paragraph 9) calls a physician's cluster of cases "not as a misfortune, but a crime"; discuss this as Holmes's moral argument, not as evidence. The texts contain no slurs. Holmes's conclusion was later confirmed: in Vienna in 1847, Ignaz Semmelweis had doctors wash their hands in chlorinated lime solution, and deaths in his clinic fell sharply; the germ theory later explained why. Puerperal fever is now known to be caused mainly by bacteria, especially Streptococcus pyogenes.

   Homework passage. The homework uses the end of Holmes's essay, below: his conclusions, stated as eight recommendations to physicians.

   1There may be some among those whom I address who are disposed to ask the question, What course are we to follow in relation to this matter? The facts are before them, and the answer must be left to their own judgment and conscience. If any should care to know my own conclusions, they are the following; and in taking the liberty to state them very freely and broadly, I would ask the inquirer to examine them as freely in the light of the evidence which has been laid before him.

   21. A physician holding himself in readiness to attend cases of midwifery should never take any active part in the post-mortem examination of cases of puerperal fever.

   32. If a physician is present at such autopsies, he should use thorough ablution, change every article of dress, and allow twenty-four hours or more to elapse before attending to any case of midwifery. It may be well to extend the same caution to cases of simple peritonitis.

   43. Similar precautions should be taken after the autopsy or surgical treatment of cases of erysipelas, if the physician is obliged to unite such offices with his obstetrical duties, which is in the highest degree inexpedient.

   54. On the occurrence of a single case of puerperal fever in his practice, the physician is bound to consider the next female he attends in labor, unless some weeks at least have elapsed, as in danger of being infected by him, and it is his duty to take every precaution to diminish her risk of disease and death.

   65. If within a short period two cases of puerperal fever happen close to each other, in the practice of the same physician, the disease not existing or prevailing in the neighborhood, he would do wisely to relinquish his obstetrical practice for at least one month, and endeavor to free himself by every available means from any noxious influence he may carry about with him.

   76. The occurrence of three or more closely connected cases, in the practice of one individual, no others existing in the neighborhood, and no other sufficient cause being alleged for the coincidence, is prima facie evidence that he is the vehicle of contagion.

   87. It is the duty of the physician to take every precaution that the disease shall not be introduced by nurses or other assistants, by making proper inquiries concerning them, and giving timely warning of every suspected source of danger.

   98. Whatever indulgence may be granted to those who have heretofore been the ignorant causes of so much misery, the time has come when the existence of a private pestilence in the sphere of a single physician should be looked upon, not as a misfortune, but a crime; and in the knowledge of such occurrences the duties of the practitioner to his profession should give way to his paramount obligations to society.

Differentiation Strategies

Assessment Guidance

1. Question 1 of 20 · Multiple Choice

   In T3, paragraph 1, a practitioner "instantly changed" his clothes and "met with no more cases of the kind." Which conclusion does this evidence most directly support?

   AThat washing the hands prevents the disease in every case BThat his clothes may have carried the disease to his patients CThat the disease came from the air of that neighborhood DThat every woman he had delivered would have caught it

2. Question 2 of 20 · Multiple Choice

   Why is the case of the two partners in T3, paragraph 2, strong evidence that the elder practitioner was carrying the disease?

   ABecause it reports more deaths than any other case in T3 BBecause a physician told the story, so it must be accurate CBecause it happened in winter, when fevers were widespread DBecause only the attendant changed, and cases followed him

3. Question 3 of 20 · Multiple Choice

   Which added information would most strengthen the partner case in T3, paragraph 2, as evidence?

   AHow many births the partner attended, and the practice's usual cases a month BThe name of the physician who met the elder practitioner in consultation CA description of how upset the elder practitioner was when he told the story DThe kind of case the two physicians had met in consultation to discuss

4. Question 4 of 20 · Multiple Choice

   T3, paragraph 3, reports that four cases "occurred in one month in the practice of one medical man, and all of them terminated fatally." What does a reader most need before counting this as evidence that he carried the disease?

   AThe names and ages of the four women who died that month BThe season of the year in which the four cases occurred CHow many cases other medical men nearby saw that month DThe medical school at which that medical man had trained

5. Question 5 of 20 · Multiple Choice

   In T3, paragraph 1, Gooch says the other practitioners of the neighborhood were "not more skilful or more busy." Why does this phrase strengthen his reasoning?

   AIt shows that the other practitioners were careless about their clothes BIt proves that the disease could not arise in any other way CIt rules out skill and workload as the reason the cases clustered DIt shows that the patients of the one man were all from one street

6. Question 6 of 20 · Multiple Choice

   What is the main weakness of the washerwoman evidence at the end of T3, paragraph 1?

   AIt links two deaths to her but counts no other patients, hers or other nurses' BIt is about a nurse, so it cannot bear on Holmes's claim about physicians and nurses CIt says the neighborhood stopped employing her, which proves she was the cause DIt describes her washing linen, which has nothing to do with how the fever spread

7. Question 7 of 20 · Multiple Choice

   Using the results in T4, paragraph 3, about how many liters of water did Bed 1 and Bed 2 each use for every kilogram of tomatoes they gave?

   AAbout 7.3 liters for Bed 1 and about 13.8 liters for Bed 2 BAbout 136 liters for Bed 1 and about 72 liters for Bed 2 CAbout 72 liters for Bed 1 and about 136 liters for Bed 2 DAbout 2,510 liters for Bed 1 and 1,380 liters for Bed 2

8. Question 8 of 20 · Multiple Choice

   Which fact in T4 most weakens the memo's comparison between the two beds?

   ABoth beds grew the same tomato variety, planted on the same day BEach bed had its own water meter to record the water it used CThe district set its 30 percent target before the test began DBed 2 is shaded after 3 p.m., while Bed 1 is in full sun

9. Question 9 of 20 · Multiple Choice

   T4 says the $180 kit "will pay for itself in the first summer." Using paragraphs 3 and 4, about how much would drip save in one summer across all eight beds, if every bed saved as much each week as Bed 2 did?

   AAbout $52.73, so the kit would take about 3.4 summers to pay for itself BAbout $22.60, so the kit would take about eight summers to pay for itself CAbout $2.83, so the kit would take more than sixty summers to pay for itself DAbout $6.59, so the kit would take about twenty-seven summers to pay for itself

10. Question 10 of 20 · Multiple Choice

    Bed 1 gave 18.4 kg of tomatoes and Bed 2 gave 19.1 kg. How far does this support the memo's statement that drip "did not lower the harvest"?

    AFully: the drip bed gave more tomatoes, which proves drip raises harvests BNot at all: harvest numbers from one garden are too small to mean anything CPartly: the drip bed did not do worse here, but one bed each cannot rule out an effect DPartly: the drip bed gave less, but the difference of 0.7 kg is too small to notice

11. Question 11 of 20 · Multiple Choice

    Which change to the test would most strengthen the memo's recommendation?

    AAsk the garden club members whether they liked watering with drip lines BMeasure Bed 2's water use more precisely, to the nearest tenth of a liter CFit all eight beds with drip lines first, then compare with last summer DTest several beds of each kind, with each method given equal sun

12. Question 12 of 20 · Multiple Choice

    Diagram 2 charts the results in T4, paragraph 3. Which reading of the chart best supports the claim that the saving was steady rather than a result of one unusual week?

    ABed 2 used less water than Bed 1 in five of the six weeks BBed 2 used less water than Bed 1 in every week, by 180 to 205 liters CThe gap between the beds grew larger every week of the test DBoth beds used the most water in week 4, the hottest week of the test

13. Question 13 of 20 · Multiple Choice

    T1, paragraph 4, says one midwife delivered 30 women and 16 caught the fever, while the other midwives delivered about 380 women a month. If the fever had struck the other midwives' patients at the same rate, about how many cases would they have had in a month?

    AAbout 203 BAbout 16 CAbout 13 DAbout 24

14. Question 14 of 20 · Multiple Choice

    In T1, paragraph 5, Roberton notes that "little more than half the women she delivered during this month took the fever" and that "on some days all escaped." How does this detail work in the argument?

    AIt weakens Holmes's claim, because a contagious disease would strike every woman BIt shows that the midwife was careful on some days and careless on others CIt answers an objection: other infectious diseases also spare some people DIt proves that the disease was spread through the air rather than by touch

15. Question 15 of 20 · Short Answer

    Holmes claims (T1, paragraph 2) that the disease is "frequently carried from patient to patient by physicians and nurses." Rate how strongly T3 as a whole supports that claim. Quote two pieces of evidence and name one limit.

    Show model answer

16. Question 16 of 20 · Short Answer

    T4, paragraph 4, ends: "Drip also keeps the leaves dry, so we expect fewer leaf diseases on the tomatoes." Is this part of the recommendation supported by evidence, by reasoning, or by neither? What would the club need to show it?

    Show model answer

17. Question 17 of 20 · Short Answer

    Rewrite the recommendation in T4, paragraph 4, in two or three sentences so that it claims only what the memo's evidence supports.

    Show model answer

18. Question 18 of 20 · Short Answer

    Roberton's evidence in T1, paragraph 4, rules out other explanations for the Manchester cases. Name two explanations it rules out, and quote the words that rule out each.

    Show model answer

19. Question 19 of 20 · Short Answer

    Compare the evidence in T1, paragraph 4, with the evidence in T3, paragraph 3. Which gives stronger support to Holmes's claim, and why?

    Show model answer

20. Question 20 of 20 · Short Answer

    Holmes (T1) and the garden club (T4) both ask readers to change what they do. Using the four questions in Diagram 1, explain which recommendation is better supported by the evidence each text gives. Name one strength and one weakness of each.

    Show model answer

These standards connect to RST.9-10.8: prerequisites to review first, parallel standards at the same level, and next steps that build on it.

Standard text: Common Core State Standards for English Language Arts & Literacy. © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.