Sample Dimensions Essay: Dean Baird


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Sample Dimensions Essay: Dean Baird

  1. 1. Dimensions of Outstanding Teaching Written ResponseDimension One: Mastery of mathematics or science content appropriate for the grade leveltaught.The narrative for Dimension One should be no more than four pages.1a. Discuss the mathematical or scientific ideas that are fundamental to understanding the chosentopic or concept. Why is the sky blue? The primary physical concept of the lesson is the atmosphericscattering of light: Rayleigh scattering, to be specific. Diatomic nitrogen and oxygen moleculesin the atmosphere scatter light in a manner that is frequency-dependent. Ultraviolet light isscattered best. From there, scattering decreases as frequency decreases. In the visible spectrum,violet is scattered most and red is scattered least. This would suggest that the daytime sky shouldbe violet. But the physiological principle of visual sensitivity also comes into play. We are mostsensitive to light near the center of the visible spectrum, corresponding to yellow-green. Oursensitivity decreases as the color of light approaches either end of the spectrum, red or violet.While violet light is scattered better than any other color, our eyes are not very sensitive toviolet. While our eyes are most sensitive to yellow-green light, yellow-green is not scattered verywell in the atmosphere. Blue is the compromise of scattering and visual sensitivity. That is, blue is scattered wellenough and our eyes are sensitive enough to blue to make it the color of the daytime sky. Scattering of the shorter wavelengths of visible light leads to sunrise and sunset skiesdominated by longer wavelengths. The geometry of sunrise and sunset requires sunlight to passthrough a thicker layer of atmosphere before reaching observers on the surface of the planet. Theshorter wavelengths (violet, blue, green, and even yellow) are scattered out from the sunlight byPAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 1Name: Dean Andrew Baird Teacher ID 24484
  2. 2. the time it reaches observers. Only the longer wavelengths (orange and red) penetrate deep intothis relatively thick layer of air.1b. Explain why this topic or concept is important for students to learn and how it relates to morecomplex concepts that students will encounter in subsequent lessons, grades, or courses. The question of why the sky is blue is an age-old mystery that puzzles anyone with aninquisitive mind who looks up at the daytime sky. It would be a shame for a student to emergefrom a year-long, high school physics course not knowing the answer. The fact that anoperational understanding of the blue sky requires the knowledge and balance of two factors—frequency-dependent scattering and the sensitivity variation of human vision—makes this achallenging lesson. Many details of scattering go beyond the scope of this lesson: why is it thatnitrogen and oxygen molecules resonate at ultraviolet frequencies? Resonance, itself, is a topicexplored in our AP Physics 2 course, where we try to unlock some of the secrets of musicalinstruments, the destruction of the ill-fated Tacoma Narrows Bridge, and how modern buildingcodes attempt to limit destruction caused by earthquakes. Knowledge of mechanical resonanceprovides a scaffolding that is helpful for understanding electromagnetic resonance, like thatfound in inductor-resistor-capacitor (LRC) circuits. Students who study atmospheric optics willadd deeper findings to their understanding of Rayleigh scattering. They will learn the role of MieTheory in explaining the color of clouds and scattering caused by particulate matter in theatmosphere. They will also learn why the light scattered to create the blue sky is also polarized tovarious degrees. Our high school physics understanding of the blue sky is a beginning, not anend.1c. Discuss the misconceptions or misunderstandings that students typically have with regard tothis topic or concept.PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 2Name: Dean Andrew Baird Teacher ID 24484
  3. 3. Misconceptions for why the sky is blue are widely—if not firmly—held. Most students(and people in general) believe the blue sky is somehow a reflection of the ocean. If pressed onthe matter, they will suggest that the ocean is blue because it is a reflection of the sky. Studentswho live near an ocean are hard-pressed to explain blue skies over places, such as Kansas, thatare far from any ocean. More informed students will suggest that blue light is scattered best inthe atmosphere. This idea is closer to the accepted reason, but still falls short since it’stechnically incorrect (violet is scattered better than blue), and it fails to acknowledge the role ofhuman visual sensitivity. Prior to this lesson, most students were not aware that their eyes aremore sensitive to some colors than to others. This variation is not intuitively obvious, and it wasprobably never taught in their previous science courses.PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 3Name: Dean Andrew Baird Teacher ID 24484
  4. 4. Dimension Two: Use of instructional methods and strategies that are appropriate for thestudents in the class and that support student learning.The narrative for Dimension Two should be no more than four pages.2a. Describe the instructional approaches you used to help students understand the topic orconcept chosen in Dimension One. My lesson is a combination of audio-visual presentation, demonstration, and lab groupactivity. It begins by inviting students to record their prior knowledge about why the sky is blue.There is an opportunity to question commonly held beliefs. With the preconceptions foundwanting, we begin our guided inquiry. We acknowledge that “sky” is just air: primarily nitrogenand oxygen, and is colorless and transparent [Supplemental Page 1, Figure 2]. By looking atphotographs of the nighttime sky and daytime sky, we conclude that sunshine is a keycomponent to the blue sky [Figures 3 and 4]. By looking at an image of a sunlit lunar landscape[Figure 5], we conclude that air is another key component of the blue sky. At this point, we mustdelve into the sophisticated idea of scattering. The actual frequency-dependent scattering of lightis difficult to show in a classroom setting, so we detour into demonstration involving a pair ofresonant tuning forks [Figure 7]. We see that one tuning fork can be used to excite a secondtuning fork into vibration. The concept of resonance is briefly described. In this case, the soundwaves that traveled from the first tuning fork to the second tuning fork were scattered when thesecond tuning fork went into vibration [Figure 8]. The success of the resonance (and thereforethe scattering) depends on the match of the natural frequencies of the two tuning forks. A hypothetical question is then posed. Consider an array of various tuning forksassembled across from an array of uniform, identical tuning forks. If all the forks in the “varietyarray” were struck, would the forks in the “uniform array” be set into vibration? The answer is“yes,” since there would be matches to the uniform forks in the variety-fork array [Figure 9].PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 4Name: Dean Andrew Baird Teacher ID 24484
  5. 5. The sun is then represented as an emitter of a spectrum of colors [Supplemental Page 2,Figure 10]. The reaction of atmospheric molecules to spectral colors is illustrated [Figures 11–13]. Violet is shown to scatter best and red is shown to scatter worst. The sensitivity of thehuman eye is then discussed with supporting graphs [Figures 14–15]. Our eyes’ peak sensitivitylies at the yellow-green center of the visible spectrum, and drops off toward the red and towardthe violet. We conclude that the blueness of the sky is a compromise between scattering andsensitivity. Violet is scattered best, but we’re most sensitive to yellow-green. So the daytime skyis blue. Next we simulate our own skies using “skinny fish tanks,” water, scattering agent (Mop-and-Glo), and small, bright flashlights [Figure 16]. In doing so, we see that blue light scattersnear the point of entry while orange and red light to passes further into the “atmosphere.” Nowwe can discuss how the same mechanism that produces the daytime blue sky also produces redskies at sunrise and sunset [Figures 17–18].2b. Explain how you identify and build on students’ prior knowledge, and how this knowledge isaddressed in your video and in your general teaching strategies. Prior knowledge is explicitly elicited in the lesson [Video 0:00-3:30]. Since studentsmight be hesitant to record preconceptions as their own, they are asked to record what they thinkother people might think about why the sky is blue. Students are generally uncomfortablecommitting to their prior knowledge in physics. They’ve been wrong about something at somepoint in the year. And even though there was no penalty for holding or expressing an incorrectpreconception, their reluctance to commit is human nature. Ascribing preconceptions to a thirdparty allows them to record it on paper while not feeling culpable if the idea proves false. Othertechniques used to bring out students’ prior knowledge include “checking your neighbor”(discussing the matter with a classmate), pre-lab questions (usually completed as homework),and the use of clickers with carefully constructed presentation surveys. During the lesson or uponPAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 5Name: Dean Andrew Baird Teacher ID 24484
  6. 6. its completion, the prior knowledge can be acknowledged as being correct, incorrect, or perhapssimply incomplete. In this lesson, I incorporate a misconception into the presentation [Video2:00]. There is a trap in physics instruction as tempting as it is troublesome. That trap is theheavy reliance on the discrepant event. While there is sometimes value in presenting ademonstration whose outcome challenges strongly held misconceptions, it is possible to overusethat technique. Students who feel they were fooled into errant predictions become weary of suchtrickery and wary of future demonstrations. Some adopt a practice of intentionally predictingoutcomes they think are wrong. Physics becomes the class where nothing works the way itshould. In general, it can create a negative tone in the class. I prefer to make the most of a limiteduse of the discrepant event. Like the tastiest chocolate mousse, a little goes a long way.2c. Discuss the instructional strategies and techniques you use to meet the learning needs of allstudents, challenging those with stronger knowledge while ensuring learning for lessaccomplished students. The classroom seating arrangement allows for eight lab groups of four students each. Wechange seats every four weeks. When we do, I allow students limited choice over their seatinglocation in a process that ensures each lab group will have one student from each quartile basedon course performance. That is, every group of four will have one student each in the 1st, 2nd, 3rd,and 4th quartile of academic performance in the course. Students are not made aware that this isthe goal, since announcing the goal would compromise confidentiality protocol. (Some studentsmight figure it out, but I change the grouping criterion on rare occasions to keep from making ittoo obvious.) When labs are collected for grading, only one lab is picked up from each group. Noone in the group knows which lab will be collected, but everyone in the group is given the scoreearned by that lab write-up. Lab partners therefore check each other’s work in a collaborativePAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 6Name: Dean Andrew Baird Teacher ID 24484
  7. 7. manner. The strongest students make sure the weakest students keep up with the content of thelab. No partner is left behind. Another measure taken to ensure success across the spectrum is our Test CorrectionJournal process. A unit test is given and subsequently scored. During the following unit, theanswer documents and tests are returned to students during class. Students record journal entriesfor each test item they missed. If they missed eight items, they write eight entries. The entriesexpress the correct answer, using a complete statement that makes sense on its own. During thenext unit after that, a 10-item quiz is given. It’s made of items from the original unit test, nowtwo units past. Students surrender their journals to take the quiz. If they get all 10 quiz itemscorrect, I give them back half of the points they missed on the original test. Continuing with astudent who missed eight items, they likely missed 40 points, so their original score was 60.With a perfect score on the quiz, they will earn back 20 points so that their score on the originalunit test becomes an 80. If their original score had been 90, they could have raised it to a 95. Thebenefit is not an all-or-nothing proposition. It is pro-rated: students who score, say, 6 out of 10on the quiz earn back 60% of half the points they missed. As cumbersome as it sounds, Excelmakes the accounting simple. The thrust of the process is that the weakest performers on the testhave the greatest opportunity for gain, but one can never recover everything they missed in thefirst attempt. Are the strongest students left out in this process? No. During the journalingprocess, test forms and student answer documents are returned to students, but answer keys arenot made available. Students must learn the correct answers and rationale from classmates. Thestrongest students become the teachers during that process. I say as little as possible during testcorrection journaling, preferring to listen as students teach students.PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 7Name: Dean Andrew Baird Teacher ID 24484
  8. 8. Dimension Three: Effective use of student assessments to evaluate, monitor, and improvestudent learning.The narrative for Dimension Three should be no more than three pages.3a. Describe how you assessed student learning and achievement for the topic discussed inDimension One and shown on the video, and how you use what you learned from the assessmentto improve your teaching. Student learning is assessed by inspection of the classroom worksheet [SupplementalPages 3-6], homework items relating to the lesson, and test items relating to the lesson. Test itemperformance on “blue sky” items is typically above average. Homework performance is mixed.Not all students choose to complete their homework assignments. Worksheet performance istypically good, although most students will have one or more missed responses. It is rare to haveany student who is completely non-responsive on the classroom worksheet. Student questions and responses during the lesson are among the best guides to futuremodifications. This lesson has evolved over the years to include an improved audio-visualpresentation, and to include student interaction with the skinny fish tanks. Based on this year’sdiscourse, I will research other animals’ visual sensitivities.3b. Discuss other specific ways that you routinely assess and guide student learning. You mayinclude examples of formative or summative techniques, including student presentations,projects, quizzes, unit exams, or other methods. Classroom guided inquiry and demonstrations always include a strong classroomdiscussion/debate element. So there is some assessment during the lessons, themselves. Somelessons involve review or are simple enough so that successful performance can be expected onthe spot. We often use our clickers during such lessons and sections (2nd period, 4th period, etc.)compete with one another to see who can get the best performance on each clicker questionposed. The use of clickers is limited so that students get very excited every time we use them.The clickers never become routine or overused. The inter-class competition element preventsPAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 8Name: Dean Andrew Baird Teacher ID 24484
  9. 9. would-be jokers from choosing wrong answers under cover of clicker anonymity. I learned thatfrom my early experience with clickers in the high school classroom. Unit tests provide the clearest evidence of student learning. But different students learndifferent topics at different rates. Content attainment among widely varying students is akin tothe settling that would occur in snow-globes filled with liquids of differing viscosities. Some getthings faster than others. (I say this as someone whose own snow-globe is filled with chillymolasses.) Unit tests are structured to revisit old topics. A typical unit test will have a majority ofquestions on the current unit, but will also include questions on topics from previous units. Thispractice, combined with the Test Correction Journal process, allows students to have repeatedexposures to material and repeated opportunities to demonstrate success. Students can also opt into another form of assessment by participating in our annual OpenHouse event, ExploratoRio. Participating students choose to build an exhibit, which is typically alow-cost version of an exhibit from San Francisco’s famed Exploratorium. The students then actas explainers of their exhibits during Open House Day, when we arrange visits from localelementary students. They again act as explainers when parents visit during Open House Night.Afterward, they must write a reflection in the form of “Notes to the Future,” which will be givento next year’s demonstrators of their exhibit. Students are assessed on the quality of the build oftheir exhibit, the enthusiasm and correctness of their explanations during visitations, and theirreflection.3c. Provide evidence of your teaching effectiveness as measured by student achievement onschool, district or state assessments, or other external indicators of student learning orachievement. My students’ performance on the California Standards Test in Physics is typically betterthan that of any other teacher’s students on any test at the school. About 65-80% of my studentsPAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 9Name: Dean Andrew Baird Teacher ID 24484
  10. 10. perform at the advanced or proficient levels. The caliber of students who elect physics is part ofthe reason for the high performance. But we typically have well over 200 students in physics.More than half the school’s graduates take physics. Unlike many schools with an Algebra 2and/or chemistry prerequisite, our only prerequisite for Physics 1 is successful completion ofAlgebra 1. We have significant variation in the intentionally big tent of physics. We do not limitthe course, as was often done in the 1950s and ’60s, to the 20 smartest boys at the school. One local school often posts Physics test results showing 90% or more of its students asadvanced or proficient. Closer examination reveals that far fewer students in the school (whoseoverall enrollment is similar to my school’s) take the test. The number of students performing atthe advanced or proficient level is nearly equal at both schools. My Advanced Placement Physics 2 students take the Physics B Examination at the end ofthe school year. Over 90% of our candidates pass with a score of 3 or better. They have alsocompeted in the American Association of Physics Teachers’ (AAPT) Physics Bowl competitionexam since 1991. The AAPT recognizes the two top schools from each division (first-year orsecond-year students) in each of 15 regions throughout North America. My students placed firsttwice, and they placed second twice. Only one other school in the area has ever placed in PhysicsBowl, placing second one time. My students have performed well in the Science Olympiad’s Physics Lab event,achieving medal recognition in regional, state, and national competition. One of my students, Jason Kamras, was recognized as National Teacher of the Year in2005. I was very proud of him claimed no credit for an accomplishment that was his, alone. Butin post-recognition interviews, he acknowledged me as one of two teachers who deeplyinfluenced his drive toward professional excellence. Such things bring teachers quiet tears of joy.PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 10Name: Dean Andrew Baird Teacher ID 24484
  11. 11. Dimension Four: Reflective practice and life-long learning to improve teaching and studentlearning.The narrative for Dimension Four should be no more than two pages.4a. Discuss the more successful and less successful aspects of the instructional activities shownin the video and discussed in the narrative, and describe what you might do differently toimprove student learning. The lesson’s greatest impact comes when students create a simulated atmosphere in the“skinny fish tanks” [Video 32:55]. They can see the spatial sequence of color scattering, whichnot only accounts for the blue daytime sky, but also the orange-red skies of sunrise and sunset. Ashortcoming of the lesson is that it is heavy on teacher-talk and content delivery. The animatedgraphics of the presentation help in this regard. I must confess to running the lesson a bit fasterthan my usual pace out of awareness of the video camera. Modifications for future use wouldlikely include slowing down. An extension question could be added: What if infrared, notultraviolet, were scattered best in the atmosphere, but our eyes maintained their currentsensitivity? (The sky would be orange.) I should research the visual sensitivities of animals tolearn more about how they might perceive the color of the sky; students wanted to know this.4b. Describe how reflection on your teaching practices helps you improve your classroominstruction. You may provide examples of lessons or activities you revised based on thisreflection. My curriculum consists of materials of my own making. While curriculum creationrequires a significant investment of time and energy, it also allows me to easily modify materialswhen needed. This flexibility is useful in improving laboratory activity instructions. While Imight think my instructions are perfectly simple and clear in the first operational document Iproduce, I often find students bog down or take a wrong turn somewhere. Modifying thedocument electronically while the problem is fresh in my mind ensures next year’s students willhave a smoother experience.PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 11Name: Dean Andrew Baird Teacher ID 24484
  12. 12. Sometimes a classroom discussion will follow a tangent that is, in fact, a valuableapplication or extension of the lesson at hand. Again, simple modification of the documentensures that we will wander off on that fruitful tangent again next year. Some lessons end in frustration for students and instructor alike. Assuming the content inquestion cannot be removed from the course, it becomes critical to revise the lesson. It is often amatter of breaking the subject down into smaller, more manageable steps of content acquisition.Sometimes an approach must be abandoned in favor of a new one. For example, incorporation ofa computer simulation (such as those offered free of charge from the University of Colorado’sPhET program) can draw students into an otherwise daunting topic.4c. Using one or two of the professional development experiences cited in your résumé, describehow your participation in these activities has improved your teaching and enhanced studentlearning. I attended my first American Association of Physics Teachers national meeting in June,1989. There I attended workshops led by Jim Minstrell (Mercer Island High School) and DeweyDykstra (Boise State University). Their sessions opened my young eyes to a more constructivistand inquiry-based approach to classroom instruction and laboratory activities. Their impact wassignificant: I have incorporated those approaches in the curriculum materials I have written sincethen. While leading a Physics Teacher SOS workshop this year on heat, sound, and waves, oneof the participants mentioned the idea of constructing a wave machine out of gelatin candies. Isubsequently researched the design, modified it, and assembled the materials to try it with myown students. They loved it! And they did learn something about wave mechanics along the way.Having seen some online videos of various attempts, I created one to add to the mix. Since Ichose Dots as the gelatin candy, my lab and video are called “Connecting the Dots.”PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 12Name: Dean Andrew Baird Teacher ID 24484
  13. 13. Dimension Five: Leadership in education outside the classroom.The narrative for Dimension Five should be no more than two pages.5a. Describe how you have supported other teachers, student teachers or interns throughactivities such as induction, mentoring, leading professional development activities, or co-teaching. I support California physics teachers through the Physics Teacher SOS workshopssponsored by the Northern California and Nevada American Association of Physics Teachers(NCNAAPT). For over a decade, PAEMST honoree, Paul Robinson, and I have led day-longworkshops sharing wisdom earned over our years of experience. We start with a rough outline,but allow our participants to direct the discourse where possible. We show demonstrations anddiscuss presentation techniques. Guidance is provided on scope and sequence, standards andassessment, equipment acquisition and management, and any other area that weighs on ourparticipants’ minds. We give participants as much useful curriculum and apparatus as possible.Participants get laboratory manuals, green lasers, hand-crank generators, ball and ring sets,constant velocity cars, flying pigs, rainbow glasses, and much, much more. We also give specificinstruction on how best to use each item in our “goodie bags.” Mostly we try to convey ourexcitement for teaching physics. Robinson and I (and our hundreds of happy participants) agreethat these “agenda-free” workshops are more valuable than most professional developmentopportunities for physics teachers. This past year, I spun off part of what we do as a workshop for the AAPT’s SummerMeeting in Portland, Oregon. There, I was able to share ideas on what physics teachers can do onthe first day of school, Back-to-School Night, and Open House. Open House is an opportunity toturn the classroom into a miniature hands-on science museum. The first day of school and Back-to-School Night can be designed around an idea I learned from Cal Poly Pomona professor andPAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 13Name: Dean Andrew Baird Teacher ID 24484
  14. 14. author, John Jewett: “Physics Begins With an M: Mystery, Magic, and Myth.” Thecorresponding presentation stirs curiosity by posing questions (such as “Why is there air?” and“Why is the sky blue?”), demonstrating strange things (like Lenz’s Law or Pepper’s Ghost), andcalling out myths (such as “Rubber tires protect occupants if a car is struck by lightning”). Allwithout explanation. Some students express frustration from all the questions posed yet notanswered. It is an engaging way to begin the year and each unit throughout the year.5b. Describe how you contribute to educational excellence at the school, district, state, ornational level. My students routinely give me high marks for my presentations, so I gave a workshop atmy school showing teachers good and bad PowerPoint techniques. When my district wasadopting state standards, I led a team that developed a series of high-quality, standards-alignedtest questions. As a member of the state’s Assessment Review Panel, I evaluate potential statetest questions for validity and alignment to state standards. I argue vigorously in favor ofquestions I find valuable and against questions I find fault with, all in the hope of best servingCalifornia. I served a similar role on the AAPT’s Examinations Editorial Board, although thatbody also developed test items. I present important issues to my colleagues in the NCNAAPT inhopes of informing and inspiring conversations. My most widely known and valuedcontributions come through the extensive curricular and extra-curricular resources I have createdand made available at my website, In addition to physics content, worksheets,demonstrations, video questions, and labs covering our two-year physics and AP Physicsprogram, I have links to my Blog of Phyz, Web Video for the Classroom (“YouTube Physics”),Skepticism in the Classroom, High-Speed Video Clips, and much more. I find it rewarding tocreate and share the resources, and it is rare for a week go by in which I do not receive athoughtful thank-you note via email from someone somewhere [Supplemental Page 7].PAEMST 2011 - Dimensions of Outstanding Teaching Written Response Page 14Name: Dean Andrew Baird Teacher ID 24484