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TEACHER: All right. What do we think? Raise your hands. Were the scientists correct? Uh, do— do dogs, under high stress levels, have more cor— do strangers and unexpected noises cause dogs more stress? And will they have higher levels of cortisol? What do we think? Treasure?

STUDENT: Yes.

TEACHER: I think so. I would agree. How— anybody disagree? Anybody disagree? Put your hands up.

STUDENT: You’re puttin’ your hand up, so you disagree.

TEACHER: Fine, I’ll keep my hand down. All right, good. So we’re all in agreement that the hypothesis was correct. Strange noises and, uh, strangers can cause the dogs more stress, m’kay?, and they will have higher cortisol levels. All right, prove it to me. Somebody tell me, what was your evidence to prove it? Joel, tell me what you think.

STUDENT: That in procedure number one, the dogs are— are low stressed out because the ow— the owner of the dogs stayed with them. In procedure number two, it was a higher stress ’cause they were, like, with the, um, stranger…

TEACHER: Okay.

STUDENT: … And in procedure number three, it was also a high stress ’cause they were still with the strangers.

TEACHER: All right.

STUDENT: And then in procedure— in procedure number four, it was a low stress because the owner came back to them.

TEACHER: All right. So if we take a look— So Joel’s sug— suggesting that the first was low stress because they were with their owner, right? Then he’s suggesting after procedure number two, this was a high stress environment because there was no owner with them. All right? And then he said that after step number three was also high stress because of the proce— the scientist blew a whistle and that, we assume, would be a high stress environment ’cause it’s a lot of noise. And then chewing on their favorite toy was a low stress environment. It’s something they’re familiar with. Now, how do we know that Joel is correct? What does our data— so—

STUDENT: I disagree.

TEACHER: Joel thought ahead and said, “Well, I think number one was low stress. Steps two and three were high stress, and step four was a low stress test.” How do we know that the— the dogs actually do experience more stress? Melanie.

STUDENT: Uh, actually, I think that, um, in the initial level, it was kinda high because I think that, um, they— they were entering a place that they’d never been to. So that their— ’Cause the Chihuahuas, that their percentages was really high. And then when the owner left, they were with— and nobody except the strangers. So they thought— probably, they thought they were gon—the dogs were gonna get hurt or something, so the percentage rose. And then the whistle caused even more stress ’cause it was a loud noise. And the percentage got even higher. And then the chew toy, bo— that— the chew toy, the percentage was lower because they were with their favorite toy and it actually helped them to relax.

TEACHER: All right. Notice what Melanie did there very well. Tearson, I’ll get your question in a second. She looked at the percentages and she said, “All right, if I look at this initial level, which we—” The dogs might’ve been a little bit nervous ’cause they were in a new place. But if you take a look, we actually saw from the first test to the second test, with no owner, the percentage of cortisol in their saliva increased. Then we went from no owner to the loud sound, and we see that the percentage of cortisol in their saliva increases again. All right? So we see that as they are more stressed out, their cortisol levels are getting higher. But then we take a look when they get their favorite chew toy, what happens to their cortisol levels?

STUDENT: It lowers.

TEACHER: It— it lowers. Which makes it suggest that they are not as stressed out. And if you look, this is pretty consistent all the way across all the dogs. With the high stress test, with a stranger or with the whistle, the cortisol levels increase. When they have their favorite toy or they’re with their owners, the cortisol levels are lower. All right? And that’s exactly— that is excellent, how Melanie did that. She went ahead and step by step, told us what was happening to the procedures. Or the percentages. Tearson.

STUDENT: I disagree with that. I think the initial— initial experiment wa— um, was higher, or it was each as, because the— the— their cortisol level was probably high because they were in a room with somebody they didn’t know.

TEACHER: Okay. So you’re suggesting that maybe their cortisol levels at the beginning could’ve been even lower, but because they were in a— even though their owner was there, they were still in a room with a stranger.

STUDENT: They were in a stranger’s room.

TEACHER: As Melanie suggests, they were in a strange room. So these cortisol levels might be a little bit higher than even normal. Okay? ’Cause the dogs are experiencing some new things that are making them stressed out.

STUDENT: And— and I, um, and I realized after I read it, that’s where my, um, on the dog’s cortisol level increased when— when they got to the chew toy experiment, the cortisol level decreased.

TEACHER: Very good. And why do you think they— why do you think, Tearson, they increased, like the no owner and the whistle, but decreased with the toy?

STUDENT: ’Cause they’re with their owner and they have their favorite toy.

TEACHER: All right, very good. So they were in a— an environment they felt comfortable with. So the cortisol levels went down. Okay?

TEACHER: Anybody have any questions? Perfect. Nicely done. I— I want— I do wanna say one thing that was really nice, that I saw an improvement over week one. Some of you are actually taking the data and actually looking at it and describing what was happening to the percentages as you went from one test to the next. And that’s exactly what you wanna do. You wanna take the tables that you see in these experiments, and you wanna put ’em into your own words. And that’s what a lot of you did today. So I was really pleased to kinda see that change over the past couple da— past couple weeks. Tearson.

STUDENT: And— and the Chihuahuas, like, the both of them had the higher percentage of cortisol.

TEACHER: Yeah, I wanted to ask you, what dog do you think— This is just kind of an extra one. What dog do you think is kind of a more stress filled dog? The husky or the Chihuahua?

STUDENTS: The Chihuahua.

TEACHER: The Chihuahua. Why would we say that? Anybody got any ideas? Shayla.

STUDENT: ’Cause they’re small and they, like— like—

TEACHER: All right, I’ll agree with you. They’re tiny little things and they look all hyper. But what does our data show us? What does our data show us? So Shayla’s using her personal experiences to be like, Well, Chihuahuas are just tiny little things. They’re always scared. But what does our data show us that makes us think that the Chihuahuas might be a more stressed out type of dog? Um, let me see, let me get somebody else. Pedro, what do you think?

STUDENT: What?

TEACHER: Why do you think a Chihuahua’s a little bit more stressed out than, let’s say, a husky? Right? So I’ll draw this blue line. Everything below the blue line is the data for the huskies— or the Chihuahuas; everything above it is the data for the huskies. What does our data tell us about which dog is more stressed out? How would we know that?

STUDENT: ’Cause the Chihuahuas— because it says that when it’s not with its owner, like, when you see the initial percentages, it was 36 and then it increased to like 57.

TEACHER: Okay.

STUDENT: But when they blew the whistle, it was 76, and the huskies were only 34.5.

TEACHER: Very good. If you take a look, in the high stress environments, all right?, without owners, the cortisol level of the Chihuahuas are much higher than the huskies; and especially if you look at the whistle, the Chihuahuas were way stressed out from the whistle, as Pedro said. When Pedro said if you look at the huskies and you— They’re a little bit stressed, but nowhere near the Chihuahuas. So our data actually supports Shayla’s personal experience that these dogs are kinda tiny and they’re probably a little bit stressed out. I’ll take Tearson and then Melanie, and then we’ll move on to science.

STUDENT: ’Cause like, um, um, ’cause like the— the Chihuahuas’ percentage for every experiment is more than 25% higher than the huskies.

TEACHER: Alright, very good. So you’re actually starting to quantify how much more stressed out the Chihuahuas are. Melanie.

STUDENT: Um, the— the Chihuahua dogs are known to be, like, really annoying. They’re always barking at you. Probably because they’re trying defend themself because they think that you’re gonna hurt them.

TEACHER: Ah.

STUDENT: And since— that’s why I think that they’re the ones with the highest percentages of cortisol level, because they’re really small and all they wanna do is to try to protect themselves.

TEACHER: All right, so maybe— maybe this experiment’s given us an insight, when we look at Chihuahuas, they’re always barking and snarling and— They don’t always look to be the most friendliest dog. And as Melanie’s suggesting, that behavior might be a result of the fact that they’re kinda always stressed out.

STUDENT: I know this Chihuahua that, um— My friend named Kevin, he owned a Chihuahua and, um, her name was Teensy, right? And she chased my little sister down the street, which I don’t even know why. My little sister was really tall for her age. And I wasn’t there, but she was hanging out with her friends and the Chihuahua— and she came up to pet the Chihuahua and the Chihuahua barked at her and then she started running, and the Chihuahua kept chasing her. And the owner accidentally let go of the leash.

TEACHER: Yeah, Chihuahuas, I’ve had a couple run-ins with Chihuahuas that have— All right, Shayla, then we do really have to move on.

STUDENT: It’s the same as Melanie. I have a Chihuahua and it chased a boy down the street. He went to the deli and I have to go chase after her.

TEACHER: Yeah, they do run kinda fast for short little dogs.

STUDENT: At least I got exercise.

TEACHER: All right. Here’s what I want you to do. Go ahead and close up your Word Generation books. Put them in the middle of the table. We’re gonna have Tearson come around and collect them. Tearson, just put ’em all on the green cart along with our vials. And then, um, Burnsley, I’m gonna have you pass out our science binders and we are good to go. Nice job.

 

- Teacher asks students to offer their conclusions, based on the data.

- Students prove their positions by referring to the data in the activity.

- Teacher summarizes the procedure with results.

- Teacher asks, "How do we know that the dogs actually experience more stress?"

- Student offers theory relating cortisol levels to the situations.

- Second student counters first student's theory.

- Teacher acknowledges the students' improvement in conveying data from a chart using their own words.

- Discussion continues about the temperament of the Chihuahua and the Husky dog breeds.

 

 

 

 

Science Lesson (from Teacher Edition)

Sign posted outside classroom

 

Students Pages 26 & 27 from Word Generation (Year 3):

Without Student Responses With Student Responses

Other students' data charts and conclusions: Student 1 Student 2 Student 3 Student 4 Student 5 Student 6 Student 7