Overview

Lesson Procedure

55-65 minutes of class time across 5 phases.

1. Warm-Up5-10 minutes
2. Direct Instruction15 minutes
3. Guided Practice15 minutes
4. Independent Practice15-20 minutes
5. Closure5 minutes

1. Warm-Up5-10 minutes

   Project the prompt. The two sentences come from a made-up nature article. Give students two minutes.

   Warm-Up Prompt

   "In the study, adult house cats slept an average of 15 hours a day. Kittens under six months old slept even longer." A classmate says, "Cats sleep a lot." Copy the exact words that back up the classmate. Then write a more specific claim the same sentences support, and underline the words that prove it.

   Take answers. "slept an average of 15 hours a day" backs up the classmate. A more specific claim is "Kittens sleep even more than adult cats," supported by "Kittens under six months old slept even longer." Name what students just did: they made a claim, found the exact words and matched the two. RST.6-8.1 asks for this in science and technical texts: cite specific textual evidence (exact words, numbers or results, with their location) to support an analysis (a statement about what the text shows or means).

2. Direct Instruction15 minutes

   Part 1: The words of evidence. Keep this table up for the whole lesson. Stress the last two rows: in science writing, an observation (what the scientist saw or measured) is usually the best evidence for a conclusion (what the scientist decided it means), and quoting the conclusion alone does not show why it is true.

   Words for citing evidence in science

   Term	What it means	Example from Passage 1
   Claim	Your analysis: a statement about what the text shows or means, which a reader could question	Worms react to vibrations, not to sounds in the air.
   Textual evidence	Exact words, numbers or results from the text that back up the claim	"they remained perfectly quiet"
   Cite	Show where the evidence comes from: quotation marks, then the passage and paragraph	(Passage 1, paragraph 1)
   Specific evidence	Evidence that names the exact trial, condition, number or result, not a general statement	"the note C in the bass clef was struck"
   Observation / conclusion	What the scientist saw or measured / what the scientist decided it means	"both instantly retreated" / "Worms do not possess any sense of hearing"
   Explanation	A sentence that says how the evidence supports the claim	The same worms ignored the piano until the sound reached them through a solid object.

   Part 2: Model with Passage 1. Charles Darwin, the scientist best known for the theory of evolution by natural selection, spent many years studying earthworms. In his last book, published in 1881, he describes tests he ran on worms kept in pots of soil in his house. Passage 1 comes from the part on their senses. Words to know: indifferent (showing no reaction), bassoon (a large wind instrument with very low notes), undulations in the air (sound waves), bass clef and treble clef (the low and high notes of a piano), sounding board (the wooden panel inside a piano that makes it louder), jars (small bumps or jolts). Read the passage aloud once.

   1Worms do not possess any sense of hearing. They took not the least notice of the shrill notes from a metal whistle, which was repeatedly sounded near them; nor did they of the deepest and loudest tones of a bassoon. They were indifferent to shouts, if care was taken that the breath did not strike them. When placed on a table close to the keys of a piano, which was played as loudly as possible, they remained perfectly quiet.

   2Although they are indifferent to undulations in the air audible by us, they are extremely sensitive to vibrations in any solid object. When the pots containing two worms which had remained quite indifferent to the sound of the piano, were placed on this instrument, and the note C in the bass clef was struck, both instantly retreated into their burrows. After a time they emerged, and when G above the line in the treble clef was struck they again retreated. Under similar circumstances on another night one worm dashed into its burrow on a very high note being struck only once, and the other worm when C in the treble clef was struck. On these occasions the worms were not touching the sides of the pots, which stood in saucers; so that the vibrations, before reaching their bodies, had to pass from the sounding board of the piano, through the saucer, the bottom of the pot and the damp, not very compact earth on which they lay with their tails in their burrows. They often showed their sensitiveness when the pot in which they lived, or the table on which the pot stood, was accidentally and lightly struck; but they appeared less sensitive to such jars than to the vibrations of the piano; and their sensitiveness to jars varied much at different times.

   Work the three examples aloud. For each, say the claim, point to the exact words, give the paragraph and say how the words support the claim. Diagram 1 shows Example 1 as a chain, and Diagram 2 shows the steps from no evidence to specific, cited evidence.

   • Claim, evidence and explanation

     Claim: Darwin's worms reacted to vibrations, not to sounds carried through the air. Find one quotation in Passage 1 for each half of the claim, and explain how they fit together.

     Result: Not sounds in the air: beside a piano "played as loudly as possible, they remained perfectly quiet" (paragraph 1). Vibrations: when the pots "were placed on this instrument, and the note C in the bass clef was struck, both instantly retreated into their burrows" (paragraph 2). Explanation: paragraph 2 says these were worms "which had remained quite indifferent to the sound of the piano," so the worms and the piano stayed the same. Only the path of the sound changed, through the air or through a solid object, and only the second path got a reaction.

   • Choosing the more specific quotation

     Claim: Darwin made sure a puff of breath could not explain how the worms acted when people shouted. Which quotation supports this better: (a) "Worms do not possess any sense of hearing" or (b) "if care was taken that the breath did not strike them"?

     Result: (b). It names the exact precaution Darwin took during the shouting trials (paragraph 1). A puff of air is felt by touch, not heard, so keeping the breath off the worms separates touch from hearing. Quotation (a) is Darwin's conclusion. It repeats the claim instead of showing how he tested it, so it cannot prove that the test was fair.

   • Evidence that limits a claim

     A student writes: "Passage 1 proves that worms react every time the table is bumped." Find the words that show the claim goes too far, and rewrite it so the evidence supports it.

     Result: Paragraph 2 says the worms "often showed their sensitiveness" when the pot or table was "accidentally and lightly struck," but "their sensitiveness to jars varied much at different times," and they "appeared less sensitive to such jars than to the vibrations of the piano." "Often" and "varied" do not mean "every time." A supported claim: "Worms often reacted when their pot or table was lightly struck, but not every time."

3. Guided Practice15 minutes

   Pairs read Passage 2, where Darwin buries food in the pots. Words to know: devoured with much relish (eaten eagerly), putrid (rotten), emission of any odour (giving off a smell), compact (packed tightly), tin-foil (a thin sheet of metal), displaced (moved), ferruginous (containing iron, so rust-colored), odoriferous (having a smell), much-coveted (much wanted). Passage 2 is one paragraph, so students cite it as (Passage 2).

   1The result was different when cabbage-leaves and pieces of onion were employed, both of which are devoured with much relish by worms. Small square pieces of fresh and half-decayed cabbage-leaves and of onion bulbs were on nine occasions buried in my pots, beneath about ¼ of an inch of common garden soil; and they were always discovered by the worms. One bit of cabbage was discovered and removed in the course of two hours; three were removed by the next morning, that is, after a single night; two others after two nights; and the seventh bit after three nights. Two pieces of onion were discovered and removed after three nights. Bits of fresh raw meat, of which worms are very fond, were buried, and were not discovered within forty-eight hours, during which time they had not become putrid. The earth above the various buried objects was generally pressed down only slightly, so as not to prevent the emission of any odour. On two occasions, however, the surface was well watered, and was thus rendered somewhat compact. After the bits of cabbage and onion had been removed, I looked beneath them to see whether the worms had accidentally come up from below, but there was no sign of a burrow; and twice the buried objects were laid on pieces of tin-foil which were not in the least displaced. It is of course possible that the worms whilst moving about on the surface of the ground, with their tails affixed within their burrows, may have poked their heads into the places where the above objects were buried; but I have never seen worms acting in this manner. Some pieces of cabbage-leaf and of onion were twice buried beneath very fine ferruginous sand, which was slightly pressed down and well watered, so as to be rendered very compact, and these pieces were never discovered. On a third occasion the same kind of sand was neither pressed down nor watered, and the pieces of cabbage were discovered and removed after the second night. These several facts indicate that worms possess some power of smell; and that they discover by this means odoriferous and much-coveted kinds of food.

   Pairs write three pieces of evidence for the claim below on sticky notes, each in quotation marks, before you show the answer. Then they check Darwin's numbers.

   • Several pieces of evidence for one claim

     Claim: in Darwin's trials, the worms found buried cabbage and onion by smell, not by luck or by coming up from underneath. Find three pieces of evidence in Passage 2 and check Darwin's numbers.

     Result: (1) The pieces were buried "on nine occasions" and "they were always discovered by the worms"; the finds add up: 1 + 3 + 2 + 1 = 7 bits of cabbage and 2 pieces of onion, 9 in all. (2) "there was no sign of a burrow" beneath them, and pieces laid on tin-foil "were not in the least displaced," so the worms did not come up from below. (3) Under very compact sand "these pieces were never discovered," but under loose sand of the same kind they were "discovered and removed after the second night," which fits the idea that a smell has to get through the soil. Keep Darwin's careful wording: the facts "indicate" that worms have "some power of smell."

   Debrief with one question: Which pieces of evidence describe how Darwin ran the test, not what the worms did? (Looking beneath the food and using tin-foil.) Scientists back up conclusions both with results and with the steps that rule out other explanations, and both count as evidence. Then hand out Passage 3, a care guide written for this page, for Activity 2.

   1Placement. Keep the bin indoors at 15-25 °C, out of direct sun and away from heaters. Do not set the bin on a speaker, a washing machine or any surface that shakes. Worms feel vibration through the bin, and a bin that shakes often may cause them to crawl up the walls and try to leave.

   2Bedding. Fill the bin about three-quarters full with shredded newspaper or cardboard. Dampen it until it feels like a wrung-out sponge: a squeezed handful should give no more than one or two drops of water. Bedding that is too dry harms the worms' skin, which must stay moist. Bedding that drips is too wet.

   3Feeding. Feed the worms about once a week. Bury fruit and vegetable scraps under 3-5 cm of bedding, in a different corner each time. Do not add meat, dairy foods, oily food or citrus peels. If last week's food is still there, wait before adding more.

   4Light. Keep the lid on. Worms move away from bright light, and in a dark bin they stay near the surface of the bedding, where the food is.

   5Weekly check. Check three things once a week: the bedding is damp but not dripping, there is no sour smell, and the worms are under the bedding, not on the walls or the lid. If many worms are on the walls, look for a surface that shakes, bedding that is too wet or a bin that is too warm.

4. Independent Practice15-20 minutes

   Students read Passages 4 and 5 on their own and answer quiz questions 1-20 with the passages open. Passage 4 is Darwin on light. Words to know: anterior extremity (front end), paraffin lamp (an oil lamp, called a kerosene lamp in the US), invariably (every time), cerebral ganglia (two small clusters of nerve cells near a worm's front end that work as a simple brain), manifest (clear), employed in (busy with), whilst (while), paired (mating), Hoffmeister (a German scientist who studied worms before Darwin). Passage 5 is a lab report written for this page; its class and data are invented.

   1When the light from a candle was concentrated by means of a large lens on the anterior extremity, they generally withdrew instantly; but this concentrated light failed to act perhaps once out of half a dozen trials. The light was on one occasion concentrated on a worm lying beneath water in a saucer, and it instantly withdrew into its burrow. In all cases the duration of the light, unless extremely feeble, made a great difference in the result; for worms left exposed before a paraffin lamp or a candle invariably retreated into their burrows within from five to fifteen minutes; and if in the evening the pots were illuminated before the worms had come out of their burrows, they failed to appear.

   2From the foregoing facts it is evident that light affects worms by its intensity and by its duration. It is only the anterior extremity of the body, where the cerebral ganglia lie, which is affected by light, as Hoffmeister asserts, and as I observed on many occasions. If this part is shaded, other parts of the body may be fully illuminated, and no effect will be produced. As these animals have no eyes, we must suppose that the light passes through their skins, and in some manner excites their cerebral ganglia. It appeared at first probable that the different manner in which they were affected on different occasions might be explained, either by the degree of extension of their skin and its consequent transparency, or by some particular incident of the light; but I could discover no such relation. One thing was manifest, namely, that when worms were employed in dragging leaves into their burrows or in eating them, and even during the short intervals whilst they rested from their work, they either did not perceive the light or were regardless of it; and this occurred even when the light was concentrated on them through a large lens. So, again, whilst they are paired, they will remain for an hour or two out of their burrows, fully exposed to the morning light; but it appears from what Hoffmeister says that a light will occasionally cause paired individuals to separate.

   1Question. Do red wiggler worms choose damp soil over dry soil?

   2Setup. We used a plastic tray 40 cm long and marked a line across the middle on the outside. One half held damp potting soil (we mixed 100 mL of water into 500 g of soil); the other half held the same soil with no water added. We covered the whole tray with one sheet of cardboard, so both halves were equally dark, and set it on a foam pad, so that bumps to the table would not reach the worms.

   3Trials. In each trial we placed 10 worms on the center line, covered the tray and waited 20 minutes. Then we counted the worms in each half. A worm lying across the line was counted as "on the line." We wet our hands with plain water before touching the worms, because soap or lotion can harm their skin, and we put the worms back in the class bin after each trial.

   4Results. Trial 1: 8 damp, 1 dry, 1 on the line. Trial 2: 9 damp, 1 dry. Trial 3: 7 damp, 2 dry, 1 on the line. Trial 4: 9 damp, 0 dry, 1 on the line. Trial 5: 8 damp, 2 dry. Altogether, 41 of the 50 placements ended on the damp side, 6 on the dry side and 3 on the line.

   5Conclusion. In every trial, more worms ended on the damp side than on the dry side. This supports the idea that these worms choose damp soil. Because the tray was dark and cushioned, light and vibration were probably not the cause. We tested only one kind of soil and one kind of worm, so we cannot say whether other worms would behave the same way.

5. Closure5 minutes

   Exit ticket: "Write one claim about worms from any passage today. Support it with one exact quotation and its passage and paragraph number, then add one sentence explaining how the quotation supports the claim." Sort the tickets into "quotes, cites and explains," "quotes but does not explain" and "paraphrases or gives an opinion" to plan the next lesson.

   Teacher note on the science and the language. Darwin's main findings hold up: earthworms have no eyes or ears, they detect vibration through the ground very well, and they sense chemicals in the soil and in their food. One detail has been refined since 1881: scientists have found light-sensitive cells spread through the skin along the whole body, most numerous at the front end and again near the tail end, so "only the anterior extremity" in Passage 4 is too narrow. The book uses British spellings (odour, colour, favourite) and older words (whilst, manifest), kept exactly as published. If your class keeps live worms, handle them gently with damp hands, return them to their bin quickly and keep them out of bright light and off dry surfaces.

   Homework passage. The homework uses Passage 6, Darwin's taste trials, printed below. Words to know: presumed (assumed), varieties (kinds of the same plant), texture (how something feels, such as tough or soft), gnawed (chewed), manifestly (clearly), lime-tree (the linden tree, not the tree that grows limes), Ampelopsis (a climbing vine), Artemisia (a group of strong-smelling plants), culinary sage (the sage used in cooking), attributed to (explained by).

   1It may be presumed that all animals which feed on various substances possess the sense of taste, and this is certainly the case with worms. Cabbage-leaves are much liked by worms; and it appears that they can distinguish between different varieties; but this may perhaps be owing to differences in their texture. On eleven occasions pieces of the fresh leaves of a common green variety and of the red variety used for pickling were given them, and they preferred the green, the red being either wholly neglected or much less gnawed. On two other occasions, however, they seemed to prefer the red. Half-decayed leaves of the red variety and fresh leaves of the green were attacked about equally. When leaves of the cabbage, horse-radish (a favourite food) and of the onion were given together, the latter were always, and manifestly preferred. Leaves of the cabbage, lime-tree, Ampelopsis, parsnip (Pastinaca), and celery (Apium) were likewise given together; and those of the celery were first eaten. But when leaves of cabbage, turnip, beet, celery, wild cherry and carrots were given together, the two latter kinds, especially those of the carrot, were preferred to all the others, including those of celery. It was also manifest after many trials that wild cherry leaves were greatly preferred to those of the lime-tree and hazel (Corylus). [...]

   2Pieces of the leaves of cabbage, turnip, horse-radish and onion were left on the pots during 22 days, and were all attacked and had to be renewed; but during the whole of this time leaves of an Artemisia and of the culinary sage, thyme and mint, mingled with the above leaves, were quite neglected excepting those of the mint, which were occasionally and very slightly nibbled. These latter four kinds of leaves do not differ in texture in a manner which could make them disagreeable to worms; they all have a strong taste, but so have the four first mentioned kinds of leaves; and the wide difference in the result must be attributed to a preference by the worms for one taste over another.

Differentiation Strategies

Assessment Guidance

1. Question 1 of 20 · Multiple Choice

   Which quotation from Passage 4 best supports the claim "The longer a light shines on worms, the more likely they are to hide"?

   A"As these animals have no eyes, we must suppose that the light passes through their skins" (paragraph 2) B"The light was on one occasion concentrated on a worm lying beneath water in a saucer" (paragraph 1) C"worms left exposed before a paraffin lamp or a candle invariably retreated into their burrows" (paragraph 1) D"they will remain for an hour or two out of their burrows, fully exposed to the morning light" (paragraph 2)

2. Question 2 of 20 · Multiple Choice

   In paragraph 1, Darwin says that focused light "failed to act perhaps once out of half a dozen trials." What does this detail tell a careful reader?

   AThe focused light worked in about 5 of every 6 trials, so it usually worked but not always BThe focused light failed in about half of the trials, so the test did not tell Darwin much CThe focused light failed in six trials, so Darwin stopped using the lens after that DThe focused light never failed, because Darwin tried it half a dozen times in all

3. Question 3 of 20 · Multiple Choice

   Darwin states that only the front end of a worm is affected by light. Which sentence from paragraph 2 describes a test that backs up this statement?

   A"As these animals have no eyes, we must suppose that the light passes through their skins" B"If this part is shaded, other parts of the body may be fully illuminated, and no effect will be produced." C"It appeared at first probable that the different manner in which they were affected on different occasions might be explained" D"it appears from what Hoffmeister says that a light will occasionally cause paired individuals to separate"

4. Question 4 of 20 · Multiple Choice

   Which of these, all from Passage 4, is Darwin's conclusion (what he decided the results mean) rather than an observation (what he saw happen)?

   A"they generally withdrew instantly" B"it instantly withdrew into its burrow" C"they will remain for an hour or two out of their burrows" D"light affects worms by its intensity and by its duration"

5. Question 5 of 20 · Multiple Choice

   A student claims: "In Passage 4, worms react to bright light no matter what they are doing." Which quotation shows that the claim is wrong?

   A"The light was on one occasion concentrated on a worm lying beneath water in a saucer, and it instantly withdrew into its burrow" B"it appears from what Hoffmeister says that a light will occasionally cause paired individuals to separate" C"As these animals have no eyes, we must suppose that the light passes through their skins, and in some manner excites their cerebral ganglia" D"when worms were employed in dragging leaves... or in eating them... they either did not perceive the light or were regardless of it"

6. Question 6 of 20 · Multiple Choice

   In paragraph 2, Darwin writes, "As these animals have no eyes, we must suppose that the light passes through their skins." What does "we must suppose" tell you about this idea?

   AIt is something Darwin watched happen when he looked through his large lens BIt is a reasoned guess that explains the results, not something he saw CIt is an idea Darwin tested and then showed to be wrong DIt is Hoffmeister's idea, which Darwin reports here without agreeing with it

7. Question 7 of 20 · Multiple Choice

   Darwin wondered whether the stretching of a worm's skin could explain why worms reacted differently on different occasions. What did he find?

   AStretched skin let more light through, which explained the different reactions BThe color of the light explained the reactions, not the skin CHe found no link between the skin and the different reactions DHoffmeister had already shown that the skin was the cause

8. Question 8 of 20 · Multiple Choice

   Paragraph 3 of a lab report says: "The seeds kept in the dark box sprouted two days later than the seeds kept in the light." Which sentence cites this evidence correctly?

   AThe report says the seeds in the dark "sprouted two days later than the seeds kept in the light" (paragraph 3). BThe report says the seeds in the dark sprouted two days later than the seeds kept in the light (paragraph 3). CThe report says the seeds in the dark "sprouted three days later than the seeds kept in the light" (paragraph 3). DThe report says the seeds in the dark "sprouted two days later than the seeds kept in the light" (paragraph 2).

9. Question 9 of 20 · Multiple Choice

   According to paragraph 1 of Passage 4, what happened when Darwin lit the pots in the evening before the worms had come out?

   AThe worms came out but kept away from the lit side BThe worms did not come out at all CThe worms came out as soon as the light was shut off DOnly the paired worms came out of their burrows

10. Question 10 of 20 · Multiple Choice

    Darwin writes that "on one occasion" he focused light on a worm lying under water, and it withdrew. How strong is this as evidence that worms under water react to light?

    AStrong, because the worm moved back into its burrow instantly BStrong, because Darwin used a large lens CWeak on its own, because it describes a single trial DWeak, because the worm did not react at all

11. Question 11 of 20 · Multiple Choice

    Why is "they will remain for an hour or two out of their burrows, fully exposed to the morning light" (paragraph 2) stronger evidence than "paired worms sometimes stay out"?

    AIt gives how long the worms stayed out and says they were in full light BIt is longer, and longer quotations are always stronger evidence CIt is Darwin's conclusion, and a conclusion always counts for more than details DIt describes a trial Darwin repeated with a lens and a lamp

12. Question 12 of 20 · Multiple Choice

    Which claim can NOT be supported with evidence from Passage 4?

    AWorms can react to light even though they have no eyes BDarwin's worms were sometimes out of their burrows in daylight CDarwin tried to explain why worms reacted differently at different times DWorms react in different ways to red light and to blue light

13. Question 13 of 20 · Multiple Choice

    A student writes: "Worms hide from light because sunlight dries out their skin, so Passage 4 shows that light is dangerous for worms." What is the main problem with this analysis?

    AIt quotes Darwin's words incorrectly and changes what he meant BIt uses the student's own knowledge, not evidence from the passage CIt cites the wrong paragraph of Passage 4 as the place where Darwin says this DIt uses too many quotations to support just one short claim

14. Question 14 of 20 · Multiple Choice

    Paragraph 2 ends: "but it appears from what Hoffmeister says that a light will occasionally cause paired individuals to separate." Which sentence reports this accurately?

    ADarwin saw that light always makes paired worms separate (paragraph 2). BHoffmeister found that paired worms never react to any light (paragraph 2). CDarwin reports Hoffmeister's view that light will "occasionally" separate paired worms (paragraph 2). DDarwin says paired worms "separate" as soon as the morning light reaches them in their pots (paragraph 1).

15. Question 15 of 20 · Short Answer

    Write a claim about how worms react to a strong, focused light. Support it with a quotation from paragraph 1 of Passage 4, then explain what the word "generally" adds to the evidence.

    Show model answer

16. Question 16 of 20 · Short Answer

    Passage 1 and Passage 4 both describe worms sensing something without ears or eyes. Write one claim that fits both passages, and support it with one quotation from each passage.

    Show model answer

17. Question 17 of 20 · Short Answer

    A classmate writes: "Darwin proved that worms are 'extremely sensitive to light' (Passage 4, paragraph 2)." Explain two problems with this sentence and rewrite it with a real quotation from Passage 4.

    Show model answer

18. Question 18 of 20 · Short Answer

    The report's conclusion in Passage 5 says: "In every trial, more worms ended on the damp side than on the dry side." Is this accurate? Check it against the results paragraph and cite the numbers.

    Show model answer

19. Question 19 of 20 · Short Answer

    The report says that "light and vibration were probably not the cause" of the worms' choice. Which two details from the setup support this, and why does the report say "probably"?

    Show model answer

20. Question 20 of 20 · Short Answer

    A news post about the class report is headlined: "Study Shows All Earthworms Prefer Damp Soil." Use the report's own words to explain why the headline goes too far, and write a headline the evidence supports.

    Show model answer

These standards connect to RST.6-8.1: 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.