More Than MagnifiersClaudia Cue & Joan Tennison |
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Clinical InterviewsClinical Interview 1, Clinical Interview 2 Clinical Interview 1: Light and Cameras Interview Questions Prior Knowledge Questions
Lesson Concept Questions
Interview Transcript
A: Light is a rainbow when it’s separate. When the different colors are together, they are white. Follow up Question: What makes light? A: sun, fire, lightning Follow up Question: Can you think of any sources that are not natural? A: a bulb
A: an energy source
A: Light spreads out. It shines all the way around. (He gestures to the area around a light in the room.) Follow up Question: (I hand him the flashlight) What if its an artificial light source? A: (He looks at the flashlight) It’s concentrated because its focused by a magnifier on the end. (He points to a thick piece of plastic on the flashlight tip) It looks like a convex lens. Follow up Question: So light comes from the source ( I point at his flashlight) and stuff that is far from the source is lit up (I point at the patch of light on the wall). How does the light move to get there? A: waves, different sources have different wavelengths, like ultraviolet or x-ray Follow up Question: What do you mean by different wavelengths? Like how are they different? A: There are more of them and they are stronger (He draws Figure 1. Wavelengths) Follow up Question: So what if the light source wasn’t in a tube like the flashlight, for example, a light bulb standing alone, how would the light move? (I draw picture of a light bulb alone) A: Out all around
A: (He turns on flashlight and I hold a marker up, which casts a shadow on the wall) Where there is mass, it makes a shadow. And the light goes; where no mass exists.
A: when light bounces off in the opposite direction
A: glass, TV, mirrors, glasses, car windows Follow up Question: Can light do anything else besides reflect? A: (Jokingly) You can use it to tan!
A: Your rods and .. something else I can’t remember… Anyway, your eye sees a basic picture and sends it to your brain. Your brain fills in the gaps Follow up question: How does your eye capture that basic picture? A: I dunno. I guess I don’t know how the eye captures the picture.
A; Takes pictures and movies.
A: You see the picture through the lens. Follow up Question: What is the lens made of? A: Glass with plastic cover around it. It is like a replica of your eye, but more high tech. Follow up Question: How is it like your eye? A: It captures a picture Follow up question: What happens to the picture inside ( I point at the lens and body of the camera). A: It develops Follow up question: What develops? A: The film
A: You use it to zoom in and out on an image Follow up Question: Some cameras don’t have a part that can zoom in and out, do these have a lens? (He nods yes. ) What do you think the lens is used for on these cameras? A. To protect the picture from light exposure Follow up question: What does the light do in camera? Why does it need protection from light? A: If light gets into the film it could mess up the picture. The light in the room has to be dark or yellow light. If film has too much light exposure, it messes up the pictures. Follow up Question: What happens if the right amount of light is coming in? A: It takes a good picture!
Figure 1. Wavelegths Interview Analysis I conducted this interview with a sixth grader from an middle class family from Austin, Texas. It is likely that the volunteer had an above average base level of knowledge for his age because his father is an photographic hobbyist. Though many of his answer were somewhat correct in their basic premise, I felt as though he was repeating things he had been told, his mannerisms betrayed that he had little familiarity with the ideas he was talking about. He had very limited knowledge of light; what I would consider to be what he could tell by looking at a diagram of the electromagnetic spectrum. He was confident in the answers on lower level ideas about light such as shadow and reflection. However he failed to mention that common objects reflect light and sited examples of glass only, this a common misconception for students his age. When I asked if light could do anything else besides reflect, he jokingly said you could tan with it, rather than talk about how light could be absorbed. He believed light needed an energy source rather than identifying light as energy or as packets of energy called photons. This is another common mistake for middle school students. Although the initial responses show an introductory understanding of light, his ideals began to break down as we discussed wavelengths. His replies along with his visual conception of the wavelengths, as seen in Figure 1. Wavelengths, revealed that he didn’t understand the differences in shape that create different types of electromagnetic phenomena. I’ll also mention that he did not refer to light as particles, which I expected that he might because of my own childhood notions. Something that interested me was that at one point, he pointed to the magnifier on the end of the flashlight and identified it, however, when talking about the camera lens, he failed to relate its magnifying power on an image. In fact, he didn’t really understand the function of the lens inside the camera. He had very little knowledge of how the camera could capture a real image and transpose it. He didn’t explain that light traveled into the camera, failing to connect light to sight. He could not explain the inner workings of the camera or how the film creates an image. I found it interesting that he believed that the lens protects the film from light exposure. He clearly does not understand that the lens is the actual tool that focuses the light and image the camera creates. He missed the fundamental idea that the lens transposes the image into the areas where the light can be recorded on film. Even more curious, he missed the concept that the camera is related to light! Although he compared the camera to the human eye, he was unable to discuss what this idea meant. He failed to mentioned that the eye has a lens, so I believe he had little idea what is meant by the camera-eye comparison. This is significant because the topic is covered within the lesson I’ve designed, but unmentioned in the More the Magnifiers manual. Further, I felt like he didn’t understand what he meant when he said film “develops” or even what film is. I should have probed him further at this point, but I was thinking about too many things at once and simply accepted his answer. In the last question I attempted to go back and illicit further ideas about film by asking what happens in the camera when the right amount of light comes in, but instead he gave me an avoidant answer unrelated to science, “it takes a good picture,” further indicating a lack of depth of knowledge on the subject. Overall, I found this process to be enlightening and informative. My interviewee was a good representative on the middle school population because he demonstrated a lack of depth and quality in his understanding of the topics of light, cameras, and lenses. Although he seemed familiar, his replies were one dimensional and often he was unable to defend his use of the correct vocabulary with adequate explanations. I would attribute this deficit in knowledge to prior direct instruction or book learning, coupled with a lack of hands on experience with the material. I will definitely be able to use the insights I’ve gained in the interviewing process to design a more effective lesson. I believe many of the misconceptions revealed by my student will be addressed within the context of the More Than Magnifiers Unit. Clinical Interview 2: Projectors PLANNING THE INTERVIEW 1. What information do I want to discover through this interview? I want to discover the misconceptions that a 7th grader has with magnifiers. I know that I had some misconceptions, and did not know the terms for many of the items that was in the Magnifiers GEMS guide. I imagine that a 7th grader has these things more fresh on his or her mind, however. 2. What do I expect the interviewee to say? Why? I expect him to know the gist of what magnifiers do, and how they work. I do not expect him to know the specifics though. 3. How can I avoid steering the interviewee in the direction of my expectations? I will ask the questions straightforward, not giving any hints as to the answers of the questions. INTERVIEW QUESTIONS Opening questions…
This interview was very difficult, but informative at the same time. Students, in general, can be very confused about science, and how science can relate to what they do everyday. The student that I interviewed, “Omar”, was a struggling science student. He comes from a low-SES background, and told me that he was only interested in “getting by” in his classes, whether that meant earning a “C” or a “D”. Omar was not very informed about magnifiers. The only thing that he seemed to know about was that his grandfather had used a magnifying glass to read the paper. This does show that he understands what magnifiers do, but that does not make Omar very scientifically aware. Omar did not understand how magnifiers worked, or how cameras worked. If he was to have the GEMS guide incorporated in his class, however, he may better understand magnifiers. I can see how using the GEMS guides in a math or science class can be helpful, reather than just using a traditional form of teaching. In addition, the GEMS guides make it simple on the teacher to incorporate inquiry-based learning. |