Dec 22, 2010

Newton's 2nd Law Survey

I got myself into some trouble yesterday while out to breakfast with a few friends. Our conversation was perfectly civil until I brought up an idea for an informal research project I'd been curious about taking on to reveal common misconceptions about Newton's 2nd law. I'd been imagining walking the streets of New York City with a microphone and performing an informal survey of how people answer a question such as, "Why does an egg break against the floor when you drop it?"

My friends and I first discussed the logistics of such an operation: whether a person on the street is more or less likely to walk hastily away if the interviewer is wearing a lab coat and bow tie... or maybe even just holding a clipboard. We agreed that it would be important to record the audio, so I could go back and listen carefully to the wording of the answers.

I then gave my friends an opportunity to respond to the question in their own words, and this is where the trouble/fun began. I got a variety of answers, such as "the force of gravity collides with the force of the floor and the egg gets caught in the middle." I expanded the question to include an egg breaking when thrown against a horizontal wall, and these answers included "the egg is too brittle withstand the force of your throw when that force encounters the resistance of wall." I, unfortunately, did not record the audio, so I can't give you the precise responses, but the most relevant point here is that I felt that their answers reflected some common misconceptions about Newton's 2nd law.

However, when I revealed to my friends that they'd answered the question incorrectly, they all got very defensive. They felt that a) I had tried to trap them into giving incorrect answers by asking an unclear question,
b) I had tempted them with incorrect reasoning by paraphrasing answers I knew were incorrect ("It sounds like you're saying..."), and c) I was nitpicking about the precise definitions of words like "force" and "inertia," rather than focusing on the conceptual validity of a response.

Their first two criticisms were certainly valid. My friends said afterward that they had been focusing on what aspects of the structure of the egg shell cause it to break, in contrast to "a steel egg." They felt that my clarifying questions interfered with their reasoning process unfairly, and that my facial expressions and tone of voice helped to convince them that these incorrect explanations were in fact correct. When they finally learned that this explanation was incorrect, they felt betrayed and angry. One friend remarked that treating a person on the street in this way might get me punched in the face.

The third criticism, however, is much more complicated. When I ask this question, I am most interested in whether the conceptual framework of the answer is correct: whether the individual is invoking the spirit of Newton's laws in their answer. However, I believe strongly that some mistakes in terminology do reflect actual flaws in understanding. If someone doesn't use the word "force" at all (the word push is equally valid in this context), I would certainly be satisfied with answer that was conceptually correct: The table had to push against the egg really hard to stop it quickly, and eggs break when they get pushed that hard. But is it possible for a conceptually valid answer to misuse the word "force" to mean inertia? I would say no, that if someone is using that same word "force" to describe the interaction between the floor and the egg, then this reflects true misunderstanding of the force concept.

If I'm actually going to go out on the street and ask people this question, I might need to change a few things:

• The question needs revision. For starters, an egg doesn't break when you drop it, it breaks with it hits the floor! Perhaps this prompt would be better: Imagine you drop a fragile object on the floor and it breaks. Describe the interactions between any objects involved that result in the breaking of the object.

• I'd need to shut my mouth and let people explain to their own satisfaction with no interference on my part. I imagine this is common practice for researchers collecting data in this way.

• I could ask for an explanation that did not use some words (force, acceleration, mass), so as to prevent confusions arising from confusions with these terms.

• I could ask a series of smaller, simpler questions to hone in more closely on where the misconceptions lay. This is the approach of a multiple choice diagnostic like the FCI, but this approach runs a risk of categorizing people's misconceptions too early in the process.

If I was able to collect adequate data, I could examine the relevance of each of these factors. Since I often use this question as an example of the validity of a conceptual approach to physics education, this would be worth pursuing. I'll keep you posted on my progress!

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Dec 13, 2010

Differentiated Instruction in Physics

Physics First provides opportunities for an interesting type of differentiated instruction, where students might arrive at a complex understanding of fundamental concepts through their exposure to a variety of experiences.

I just got back from a trip to Baltimore to observe Physics First classes. I had a chance to visit two of the fifteen Baltimore public schools now teaching CPO Physics First, but the details of this visit will have to wait until I have a chance to wrap my head around it somewhat!

In the meantime, though, I wanted to describe my experience at a monthly workshop for Baltimore physics teachers, called "Physics Works." Physics Works is a monthly gathering of physics teachers in the Baltimore public school system, and my trip happened to coincide with this month's meeting. The day's 2-hour workshop was based on planning differentiated instruction geared toward students' varied intelligences. (This idea was first suggested by Howard Gardner in 1983: humans exhibit multiple different types of intelligences: bodily-kinesthetic, interpersonal, musical, etc. An effective teacher can give students opportunities to participate in activities geared toward their personal strengths.) After discussing the varied strengths of the people in the room, we worked in small groups to complete the following task: develop a plan to teach Newton's laws that considers the multiple intelligences of students in a class.

Most groups in the room interpreted this task to mean providing students with a variety of assessments to choose from. These assessments could range from writing a physics rap to drafting a letter to Isaac Newton to analyzing of video footage from a football game. This is what the teacher running the workshop intended for us all to do, and she provided us with a handout on suggestions for creating a "menu" of options for students to choose from.

It took our group a while to notice this "menu" handout, and as a result our group interpreted the task to mean something very different. Instead of giving students a choice between assessment styles that might suit their strengths, we asked ourselves how we could exploit these intelligences to engage the students through different perspectives. We designed an activity on Newton's third law that began with students pushing each other outward in rolling chairs, to engage them through their bodies. We then imagined students breaking into smaller lab groups to discuss fictional students' interpretations of the results
*, to engage them through words and conversation. Student might then work to design an experiment to collect quantitative data on mass and change in velocity with spring-loaded carts, to engage them through manipulating objects in space. This brought up a discussion of the link between logical-mathematical intelligence and spatial intelligence in data analysis using graphs and pictures, and so on.

What was exciting to me about this activity was that the concept of Newton's third law exists somewhere at the intersection of all these related activities. Students aren't just given the freedom to choose which types of activities they identify with more than others. Instead, they are expected to engage with the physics through each of the various activities, through areas of intelligence that they both excel at and struggle with. This seems similar to
the multiple representations which lie at the heart of Modeling Instruction, discussed in the 11/17 post below.

When taken one-by-one, the "multiple intelligences" seem like a simplistic interpretation of human strengths and weaknesses, and indeed there is much to criticize in Gardner's theory. But perhaps the interaction between these intelligences is something to devote more attention to?

*These fictionalized discussions are used in Lillian McDermott and Peter Shaffer's Physics by Inquiry and Tutorials in Introductory Physics. These programs were developed by the Physics Education Group at the University of Washington, and they are both excellent. The format might look something like this for the activity discussed above:

Consider the following statements:

Student 1: A
smaller student is always going to move faster because the larger student pushes them harder. Larger people are usually stronger than smaller people, so they have more pushing power.

Student 2: The recoil effect makes the person who did the pushing move backward, but this recoil never makes that person move faster than the person they pushed because their push is directed forward, not backward.

Student 3: Whenever two people interact, they push against each other exactly the same amount. A smaller person moves away from the interaction faster because they have less inertia, it’s easier for that same push to make them move.

Do you agree with any of these students? Explain.

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Dec 7, 2010

Teacher-Driven, Student-Centered

The ninth grade physics class at this Quaker school is an example of how a creative and dedicated teacher can make extensive use of resources from a variety of places to design a unique and popular course.

I'm quite partial to the emphasis that Quaker schools place on holistic education, and I think that philosophies of Quaker education match nicely with some the ideas behind Physics First. This particular Quaker school I visited is fairly small. The 70 or so students in a typical ninth grade class are split into four sections, at 15-20 students each section. The physics class is required for graduation, so students who enter the school as a Sophmore or Junior take the physics class along with the ninth graders. The school also offers AP Physics B, which approximately 15 students a year elect to take in their senior.

The school has been teaching physics in ninth grade for many years (15+), and most sections of ninth grade physics have been taught exclusively by one teacher for the past four years. This teacher was a middle school math teacher before teaching physics, at MS104 in NY for six years and at her current school for five, after which she was recruited by the science department to take over the ninth grade class. She has a background in chemical engineering, and worked for 10 years as an engineer before deciding to get into teaching.

I'd been in touch with this teacher for a while before arranging a visit, and she was very generous about sharing the teaching materials that she uses in her course. This is especially notable because she uses a lot of different materials! Though students have access to Hewitt's Conceptual Physics text, the class seemed to be mostly built around activities and handouts that she has found in various places and sometimes altered slightly to better fit her course. (She models for her students a responsible respect for intellectual property by using material that has been distributed online for exactly this purpose, and by citing the author of a resource if she alters it from the original.) In the classes I saw, she made use of or referred to having used: a PhET simulation-based lab activity on graphs of accelerated motion, a handout on skydiving written by JL Stanbrough at Batesville High School, a clip from an episode of the Discovery Channel's Mythbusters (about Keanu Reeves and Patrick Swayze's timeless classic Point Break!), a short lab activity on dropping coffee filters taken from Hewitt's supplementary lab activities book, as well as some handouts of her own design. This type of diversity is exciting to see, and it's evidence of a class that's engaging for students.

To facilitate a discussion on the air resistance on a falling object as it approaches terminal velocity, she employed teaching method that was similar to Ron Thornton and David Sokoloff's Interactive Lecture Demonstrations, or ILDs. ILDs were initially developed for use in large classrooms where the availability of materials and time prevented students from performing their own inquiry-based labs on a topic. Students are given two copies of a handout filled with prompts for predictions and explanations relevant to a demonstration that is performed with equipment large enough to be seen by every student in the room. Before the teacher performs each step of the demonstration, students record predictions and explanations on one copy of the handout, to be collected at the end of class and checked for completion. After the demonstration is performed, students record the correct result and explanation on a copy of the handout that they keep in their notebook. She applied this method to a discussion about the shape of position, velocity, and acceleration graphs of a skydiver approaching terminal velocity. Since the size of her class was rather small, she was able to check student's guesses simply by walking around the room. I was especially impressed at one moment after students recorded their own individual guesses: She gave them permission to discuss their answers with other students in the class, and the room erupted into substantive, engaged conversation. After this, the teacher facilitated a discussion that included references to free body diagrams and a slope analysis of the graphs, and all students seemed quite invested in the explanation of what was wrong about their own graphs (almost every student drew acceleration increasing gradually from the moment of the drop, when the acceleration is the greatest at t=0s). The determined look on the faces of students who had
passionately and convincingly argued a graph that turned out to be incorrect is an excellent example of cognitive dissonance in physics education. (A note about this link: This paper from 1982 examines an approach to teaching the particle model of gases that first exposes students preconceptions, but the first half of the paper gives a nice summary of some relevant cognitive psychology. A student's interpretation of the motion graph of a falling object is certainly more removed from their understanding of the natural world than their picture of the matter they interact with every day. But in comparing their own graph to the correct graph, many students in this class were directly confronted with their own incorrect assumption that acceleration increases as speed increases. The role of identifying "alternative frameworks of understanding" in physics education is a huge topic, one that is certain to come up again in future posts!)

The summer before teaching the ninth grade physics course for the first time, this teacher attended a physics teaching workshop through the Institute for Inquiry at the Exploratorium in San Francisco, CA, during which she was exposed to a wide variety of demonstrations, labs, and online resources. She attributed a lot of her exposure to good physics teaching practices to this workshop, and maintains frequent contact with individuals she met at the program.

The course has evolved significantly since this time, but the central focus of the course has remained constant. After attending the Institute for Inquiry workshop, this teacher made the decision to cover less significantly less content than her predecessor, choosing instead to cover material in greater depth. The content of the course changes from year to year, but her decisions have been informed somewhat by conversations with other teachers in the science department. For example, she does not include thermodynamics because the chemistry class covers these concepts. The decision to remove thermodynamics from the physics class was made after the chemistry teacher taught a section of physics a few years ago. It strikes me that this sort of crossing-over of teachers between the sciences facilitates greater communication between these teachers, and can in turn allow for a more consistent presentation of science throughout a student's high school education. That is, if science teachers at a school are familiar with each other's classes, the language in which concepts are presented in different classes can be more consistent, and the logic of the PCB sequence (physics informs chemistry, chemistry informs biology) can be exploited more effectively. Furthermore, one aspect of the science program at this school that's worth noting is that the format and priority of lab reports is consistent from year to year, through the different subjects. The teacher explained that this consistency was a recent development in the science department, but it's one that was surely facilitated by good communication between teachers in the different disciplines.

The physics classes are split into three sections of Quantitative Physics and one section of Regular Physics (for students that particular difficulties with math). For students that attended Friends for middle school, recommendations on which students belong in which section are made by the middle school math and science teachers. Placement of new ninth graders is based mostly on their performance on a math diagnostic test. Tracking students with difficulty in math allows the difficulty level of the "quantitative" sections to be higher than it would be otherwise, though none of the sections of Quantitative Physics I saw had much of a quantitative emphasis at all. The primary emphasis of the physics class at the school was on conceptual problem solving and exposure to new physics concepts through experience. The tests and quizzes I saw reflected this priority, and the teacher made a point of emphasizing that the algebra-based questions students were asked to solve in her course were never the questions they had trouble with.

The classes I saw on this visit were diverse in their presentation of material, and emphasized student discussion and involvement in activities. The teacher has not attempted to use diagnostics to gauge the effectiveness of the class, but the class fits well with the progression of the classes at the school.
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Nov 22, 2010

One Teacher's Texbook-Based Course

I visited this private school a slight drive outside of New York City on a rainy day, and I got a little wet wandering around the campus for a while. I had to ask three people for directions before I was able to find the science wing. My point is that this school is well-equipped, and their campus is BIG and beautiful. The school is not predominantly a boarding school, but some students (and some teachers) live on campus. There are about 100 students in each grade. The ninth grade physics class covers a lot of material, and there is a heavy emphasis on using algebra and even trigonometry to solve quantitative problems. For students that have not had the necessary math, physics teachers teach the math that is needed for the physics class (for example, students are taught how to work in radians in their unit on circular motion and rotational dynamics). Labs make heavy use of technology (PASCO sensors, mostly), and students are given a set of instructions to follow, through which they are generally expected to arrive at an expected result by entering data into a preexisting spreadsheet. In general, the class resembled a traditional eleventh grade physics class taught at the ninth grade.

I had been in touch with the head of the science department and a physics teacher here, for quite a few months before I managed to make my visit. This teacher told me early on in our discussion that he had written his own textbook for their ninth grade course, and I found this intriguing. In talking with him, I learned that this textbook evolved out of his own personal lecture notes. It resembles a standard introductory physics texbook, with some personal touches of specific problem solving methods and terminology he is partial to. For him, this textbook falls somewhere between the difficult level of, say Giancoli's algebra-based text, and Hewitt's Conceptual Physics (He mentioned that he thought that the Hewitt book was too rudimentary for his taste.). This is the first year that they are using this textbook for all students, though ninth grade physics has been taught at the school for about six years. The class seems very popular these days, and a biology teacher who led me to the physics classroom mentioned without prompting that she loved physics first, because her bio students had a solid understanding of chemistry.

I was amazed at how much content the teacher got through in one 90-minute extended period. On their third day of discussing forces, the class began with an introduction to free-body diagrams and concluded with (a) a Newton's second law problem where an upward pull accelerates an object in opposition to gravity, emphasizing the difference between F=ma, and Fnet = ma. He used (b) a force diagram of pushing a book horizontally against a wall to introduce the idea of friction, and spent a few minutes discussing (c) what I would consider a difficult problem of the forces involved when pulling two blocks linked to each other horizontally.
This teacher is an entertaining lecturer, and students seemed engaged for the entire 90 minutes or so, even though they were in their seats for the entire time.
(The net force double arrows in examples (a) & (c) are my own addition... an old habit from my own course.)

I also observed another ninth grade teacher who has been at the school for five or six years, since the early years of their physics first implementation. This teacher was a very charismatic lecturer, and he worked to pull students into his lecture with stories about his past, and fictional narratives about Newton developing the laws of motion. Newton's laws were introduced one after another at the very beginning of the class, on what seemed to be the first day of discussing forces. Students recorded word-for-word definitions in their notes, and discussed with each other questions like, "Which way will an iPod on the dashboard of a car move when the car accelerates?"

In my conversation with the science head, I asked what discussions they'd had around using inquiry-based education. He said that they weren't sure where they stood on implementing more inquiry-style activities, but they were trying to come up with something that would fit.
When I mentioned the FCI, this teacher said he was familiar with the test, but I don't think he uses the test to collect data on the effectiveness of his own class. I get the impression that inquiry-based teaching and a focus on conceptual understanding are both gaining traction in physics classes across the country, but I think that at places with a reputation for high-powered academics (like this particular school), this focus may seem too rudimentary. Both teachers I observed are engineers by training (One also has a Master's degree in physics education.), and they seem to share the view that a difficult physics problem is a physics problem that involves difficult mathematics. Some students in the class were able to solve some tough problems, problems that my own IB Juniors would have had some challenge solving. At times, however, I noticed myself feeling defensive for having set very different priorities in my own course. In a program like the one here, where problem solving is a primary goal, would an individual teacher who wanted to devote more time to inquiry activities (at the expense of content, because inquiry takes SO MUCH TIME to do right!) feel some pressure to get their kids down to business solving more problems?
In summary, it was clear that this school was proud of their academic program, and prioritized a high degree of quantitative problem solving in their ninth grade class. Students are enthusiastic about physics, at least in part due to the very animated personalities of their physics teachers. The course fits well into their entire high school curriculum, and teachers of other subjects feel that the ninth grade course has added to the effectiveness of their own courses.
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Nov 19, 2010

Conversation with a Friend

Last Friday night at 1am (!), I ended up having a conversation about science teaching with a friend of mine who lives in DC. She is working for the American Engineering Association on nation-wide campaign to change people's views about what it means to be an engineer. Essentially, the AEA sees much-reduced enthusiasm for the profession, and they're trying to do something about that by changing the public attitude. When our nation's brightest potential physicists and mathematicians spend their time bringing the world's financial system to its knees rather than, say, solving the world's energy shortage, something is certainly wrong. It struck me that high school education provides unique opportunities for influencing students in ways that might make them more inclined to devote themselves to science or engineering.

The meat of this conversation, for me, is in the question of whether we're doing what we want to be doing with our science classes in this country. I mean, clearly we're not, but what do we want to be doing? Measuring gains on diagnostic tests, I believe, can do a good job of measuring the effectiveness of a class to truly teach student what you're trying to teach (That is, I believe that the FCI accurately reveals whether the person taking the test can be called a "Newtonian thinker."), but this certainly isn't the only measure of the success of a science class. If we're trying to encourage our students to want to devote themselves to science and engineering, then the value of an assignment where students are asked to build something with their hands can't be underestimated. Shop class is a rarity these days , and with most of the focus of NCLB or R2T on testing, it ain't making a comeback anytime in the near future.

Maybe one of the best things we can do with our ninth grade physics classes is to generate enthusiasm for the subject through content-based building projects, student-designed experiments, and projects that may not even be all that topical mostly intended to spur creative engineering in students. I considered the 2-Liter bottle rocket project in my ninth grade class to fall mostly into this third category. The project fit into nicely into the class around Newton's third law and conservation of momentum, but it was mostly an opportunity to turn students loose to research and build something cool. It took me a little while to come around to it, since I saw it as less instructive than other activities, but I kept it in the course because my students loved it so much. But after a few years I came to see the primary value of the project was simply that students were working together to build something truly badass.
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Nov 17, 2010

Modeling PF in a New Jersey Public School

The head of the science department at this public high school in New Jersey was one of a few people in my area who responded to an open request I sent out to the physics first listserve in the spring of 2010, and I'm very glad he did. The program at this school was exciting to see, and it is a rare example of a large public school that's been able to institute a successful physics first program at multiple skill levels. The program is an excellent example of successful Modeling Instruction, and students have shown significant gains on diagnostics tests and an increase in upper-level physics enrollment over previous years.

This school has been teaching physics first for quite a while (8 years) but the program has only been as successful as it is currently since they instituted Modeling Physics school-wide. When the ninth grade class began, they were essentially using a college-prep text at the ninth grade level, and this wasn't successful. One physics teacher learned about Modeling Physics at a seminar for the "It's About Time" program a few years ago, and then attended a modeling workshop at Arizona State University. He, like many others who experience Modeling Physics for the first time, came back with his perspective on science teaching completely changed, and he and the head of the science department gradually initiated a push to convert the entire ninth grade physics program to a Modeling approach. This change, as far as I can tell, took place totally independently from any other schools in their area (I find this impressive!).

This school has since become authorized to offer a workshop in Modeling Instruction on site, and this has made it much easier for them to maintain a consistent approach among their physics teaching staff. Science teachers have a four-course teaching load, and every physics teacher has been trained in Modeling. Furthermore, the department has collaboration time built into their schedule to facilitate discussions between teachers on what is working well for them. It's clear that the success of the program is a result of the department taking very seriously their responsibility to educate teachers in this unique approach to physics education, and to giving teachers this time to collaborate. All science classes take place in 90-minute periods, meeting three out of every five days.

There are over 400 students in the Freshman class, split into 20 sections, so at any given moment there are three to four ninth grade physics classes being taught. These courses are split into three tracks, called "Honors", "College Prep", and "Applications." The Applications course is taught to students who did not pass the New Jersey ASK 8 test in 8th grade (some of whom are special education students), and each of these classes is co-taught by a physics teacher and a special education teacher. The diversity and quantity of physics classes being taught make this shcool an ideal place to see Modeling in action.

In New York state, some successful physics first programs have been forced into switching back to a standard Bio-Chem-Physics (BCP) course order because of pressure to do well on the Regents, a state-standardized test. That is, since students have a difficult time passing the "Physical Setting" Regents, a test designed to be taken by high school Juniors, it has been difficult to defend Physics First to parents and administrators, since these Freshmen have a hard time passing this test. (This is a fruitful topic of discussion in itself, and I plan to devote a future post to this entirely...) In New Jersey, however, there is no state-standardized test for physics, so this particualr school has been free to continue offering the ninth grade course. In fact, reversing the order of the sciences has made it significantly easier for students to pass the required NJ state test in biology (since they end up taking biology as a Junior, and the test is designed to passed by Freshmen). Therefore, to prove the effectiveness of their science program, the school employs two different diagnostics before and after their unit on mechanics: the Force Concept Inventory (FCI) and Lawson's Classroom Test of Scientific Reasoning. The school's program has shown substantial gains in both tests. Data showing the effectiveness of physics first is still relatively rare, so these results are invaluable to the physics first community.

Since I haven't been personally trained in Modeling Instruction, I can only speak rather superficially about what I saw taking place at this school. Students are taught that a natural phenomenon, like an object accelerating, can be represented in multiple ways, but that each of these multiple representations is at best a vehicle for gaining insight into the actual phenomenon itself. The power of this seems to be that the conversations students have about how to solve a problem take place at the intersection of these different models. In the case of a standard acceleration problem, for example, students are asked to solve the problem algebraically, graphically, numerically (with a table of values), and also represent the same situation using a "motion map." I witnessed students discussing standard accelerated motion problems, not with the language of, "What's the next step I need to solve this problem?" but instead, "How does this algebraic solution connect to this graphical solution?" One or more of their multiple representations could be wrong, but the multiple representations themselves gave the students a strong footing for their discussion about the problem, and more nuanced understanding of the natural phenomenon itself.

Students in a modeling course make extensive use of "whiteboarding": recording a solution in multiple representations in a group of 3-4 students on a 2'x3' whiteboard, then presenting their solution to the rest of the class. Although I did witness one class where a teacher employed a more conventional lecture-style approach (He said he felt pressed for time to get through more material,), almost all the class time I observed was spent whiteboarding. The 90-minute periods for science classes at the school I visited also make this whiteboarding process more effective, since the process is quite time-intensive.

Physics teachers at this school are free to employ their own teaching methods and exercises. One teacher assigned a "Picture Project" where students were asked to take one picture each of subjects that demonstrated constant velocity and uniform acceleration, then write a paragraph about each explaining their picture's relevance to those topics. There were certainly differences between classes, and between different levels of instruction (Honors, College Prep, and Applications) but in general I was struck by the uniformity of teaching method throughout these levels. This is certainly due to the fact that all teachers are trained in Modeling, and are expected to teach in this style. Furthermore, it seems as though the Modeling approach is expanding into the Chemistry and Biology classes. I sat in on one Modeling Chemistry class, and glimpsed the potential of expanding this type of thinking into the rest of the high school science curriculum. If this expansion is effective, Physics First will serve as a high school student's introduction to the modeling approach.

I haven't yet had a chance to see specific results of the FCI and the Lawson from this school (and haven't yet asked...). It strikes me that the details of these results are essential to truly understanding the effectiveness of the Modeling approach. I came across an interesting paper titled Learning of Content Knowledge and Development of Scientific Reasoning Ability, in which the authors demonstrate that FCI scores do not correlate with scores on the Lawson. That is, training a student to think according to Newton's laws does not necessarily train them to think like a scientist. There's no question that this school spends more time on mechanics problem solving than many other programs do, and I'd say that the problem solving approach that they take is very well suited to solving the types of problems on the FCI or the Mechanics Baseline Test. So perhaps it's no real surprise that these students perform more successfully on these tests, since they are more familiar with these types of problems? As a big fan of the FCI, I'm still not personally sure whether these questions really test whether a class is doing what we want our high school science classes to do. However, if FCI gains DO correlate with gains on the Lawson as a result of this program, then that's a very different result indeed.

In general,
I was totally blown away with what I saw at this school, and I hope to go back to see more Modeling in action during the unit on Newton's second law. This program provides clear evidence that a successful ninth grade program at a large school is possible, if adequate resources and attention are devoted to teacher training and collaboration. The administration at this school deserves credit for giving the science department the freedom to pursue this approach.
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Nov 16, 2010

Student-Designed Experiments in an All-Girl School

This post describes my visit an all-female K-12 school on the upper east side in Manhattan. The school is small, with a class size of about 60 students in each grade, 15 students to a classroom. I spent most of a day at the school, and sat in on two ninth grade physics classes, one senior level AP-style course, and one student-teacher interview about an independent research project. What follows is a rough account of what I saw during my visit, and my impressions of what the program seemed to emphasize. The teacher I spent most of my time with took a great deal of time out of his day to discuss the program at the school, and gave me totally free access to any class I was interested in seeing.

This school has been teaching physics first for about eight years. Since students are not required to pass any external standardized test, the priorities of the class are set entirely by the department, and there is a lot of collaboration between teachers to decide what these priorities will be. Four members of the current science department have taught the ninth grade class, though there are currently only two current teachers of ninth grade. At least two of the four individuals who have taught the class through the years have degrees in biology, not physics, though they felt that there was adequate communication and collaboration within the department to make their physics teaching experience effective and enjoyable. For every science class taught by more than one teacher, teachers meet at least once a week to discuss the class.

I talked at length with one teacher about a project that students do near the beginning of the year that is entirely based on scientific process and isolating variables. This teacher called it the "whirlybird experiment," and it recalled for me the "Internal Assessments" of
student-designed experiments required by the International Baccalaureate program. (Chris Hamper has produced an extremely valuable resource for these IB Internal Assessments in Design that provides a nice overview of the focus of these assignments.) Each ninth grade class does a class-wide experiment relating two variables of a paper "whirlybird": drop height and flight time. The class then analyzes the data they collect by graphing one variable against another in Excel, and calculating a linear regression, discussing "error" etc. Students are then required to develop their own investigation into two quantifiable variables of the whirlybird, such as "# of paper clips vs. flight time," where they hold all other variables constant. To me, this exercise falls into the category of "things that ninth grade physics can do uniquely well. Physics, moreso than biology or chemisty, uses instruments and variables (stopwatches & meter sticks to measure time and distance, etc.) that students understand intuitively, so the emphasis becomes the process of doing science. This exercise communicates early on in a student's science education the message the science is a discipline based on collecting and interpreting data. Coming out of middle school, many students have developed the impression that science is something that comes out of textbook or off the internet, and a ninth grade physics class can give a student ownership of their own science education in a very powerful way. (This emphasis was also clear from the teacher's introduction to accelerated motion. At one point, he asked students to decide whether they thought a falling ball was accelerating. His follow-up question to this was, "What evidence do you have to support that claim?")

Much of the focus of inquiry-based science education seems to be on giving students this same sense of ownership of their own understanding. This type of approach develops the skill and intuition to look at a problem as a scientist would, and to expect that a scientific claim should be supported with evidence.
Perhaps moreso than any physics concepts or understanding, this skill seems to be applicable in all spheres of life.

This teacher has also done an excellent job of presenting students with a comprehensive rubric for lab grading, and making his priorities clear. He uses the class-wide whirlybird introduction as an opportunity to show them an ideal lab report, and then turns them loose to present their own findings. He does about one full lab report per term (4-6 in a year), but he expects these assignments to be substantial and comprehensive. The lab grading rubric has evolved a lot through discussion with the science department, but the priorities of a lab report change from grade to grade. The teacher felt that the differences in focus between the disciplines make it difficult to keep consistent priorities from grade to grade, but that all classes emphasized that lab reports were for presenting unique findings within a larger context of research, to reflect the structure of science outside the classroom.
The ninth grade course is called "Conceptual Physics." On the day I visited, students were studying free fall using standard equations of accelerated motion. I saw ninth graders complete a lab where they estimated the height of the room by measuring the time it took for a ball to fall this distance, and then the teacher dropped the same ball out the window to estimate the height of the physics room on the sixth floor. The questions on the test that I saw, and the problems that were being discussed in class tended to be centered around quantitative problem solving, though the teacher pointed out one question about relative velocity that asked students to "explain" how one observer could perceive the velocity of an object to be directed northward while another observer perceives the same object to be moving with southward velocity. Since kinematics tends to be heavy on quantitative problem solving I imagine my observation was skewed toward the quantitative, but the problem-solving methods I witnessed mostly stressed the procedure of how to approach an algebra problem with these variables, etc.

This procedure is something that I chose not to emphasize in my own kinematics unit, so I think I was looking closely at what this school has chosen to do with this material. I'd see this an example of a style of problem solving that is hard to do as well at the ninth-grade level as it is with older students, simply because of the limitations of a ninth grader's algebra skills. The teacher clarified to me in a recent email that he feels comfortable stressing algebraic problem solving because all ninth graders at the school have passed Algebra I by the time they take physics. (If they haven't completed an Algebra course, they enroll in summer school before their ninth grade year to get them up to the math proficiency level of their classmates.) In discussing his 12th grade physics class (designed in part to get students to pass the mechanics AP test), the teacher mentioned that he thought of this class mostly as an "applied math" course, and that this reflected a personal priority of his. I imagine that this priority extends to the ninth grade as well. (Certainly, this teacher is not alone in emphasizing quantitative problem solving in a physics class!)

In my view, the fact that the school is all-female is a positive aspect of physics at this school. In my experience with a mixed-gender physics class, boys can often dominate a discussion. This isn't because the boys are more competent with the material, but rather because they are often more eager and competitive with each other. Girls can get lost in the mix if a teacher doesn't actively pull them into a discussion. At an all-female school, it seemed that ambitious girls were free to pursue their interest in the subject without the fear that their interest will be viewed negatively by others in the class. Some girls stayed quiet throughout class discussion, but this wasn't because of a gender difference. All the physics teachers at this particular school are male, so students do not have a role model of their own gender to look up to in the subject, but they are certainly not the only school with this problem.

The ninth grade physics class at this school is popular and successful. This seems to be in a large part due to the dedication of the teachers, and these teachers have the full support of their administration. For many students, the ninth grade physics class is the only physics class they will ever take, and the course seems like a comprehensive collection of introductory physics concepts and problem-solving methods.
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Nov 14, 2010


Though I've been working on these observations since September, I'm just now getting around to creating a public record of these observations! I apologize for the delay! Much of the information here has been copied directly onto the "What's this Project?" page, so I'm sorry for the redundancy.

First, some background: My name is Joe Kremer. I have a Bachelor's degree in Physics and Russian Language from Oberlin College, and I worked teaching physics at the Brooklyn Friends School in Brooklyn, NY for seven years. For four of these years, I was working full time as a ninth grade physics teacher. I also taught IB Physics SL for three of these years. I left BFS in the fall of 2010 to pursue some other interests, and to try to get a perspective on the state of ninth grade physics education outside the walls of this one school.

My research is focused on some big questions: What does a ninth grade physics program need in order to be successful? What can ninth grade physics do well? (By this I mean really well and uniquely well, as opposed to simply "almost as good as as physics class for Seniors.") What do we want students who come out of these programs to be good at? How can we best get this desired result?

My experience at BFS was wonderful. BFS is a very small school (~50 students per grade), and I was the only physics teacher for much of my time there. I had the complete support of my administration and my department to do anything I wanted with the ninth grade class, and I was able to set the scope, depth, and focus of the class entirely to my own priorities. As such, this class was developed to a large part without much communication of any kind with others in the physics teaching or PER communities, and I became very curious to explore what teachers at other schools were doing with physics first. These observations are the result of that curiosity.

The priorities of my class were centered on developing a truly "conceptual" understanding of physics- an understanding based on a qualitative analysis of equations and problem solving with words and explanations. The concepts covered in the class varied from year to year, but essentially reflected a standard introductory physics curriculum: mechanics (forces first, kinematics and graph analysis, momentum & impulse, energy), electrostatics, electric current and circuits, magnetism, thermodynamics and the molecular model, electromagnetic radiation, oscillations and waves, and sound. Questions explored in the class ranged from "Why does an egg break when you drop it?" (A fundamental Newton's second law question: if a student can answer this question thoroughly then their teacher is doing something right!) to "Will this bulb get brighter or dimmer when I unscrew this other bulb?" (The circuits unit is provides many excellent opportunities for "conceptual" explanations of some tricky physics.) to "How do people breathe?" Students had access to Hewitt's "Conceptual Physics", but this text did not serve as their primary resource for the class. It's my feeling that the language of this text is well above the level of understanding of the average 14-year-old, and Hewitt's priorities didn't always match my own.

I came to think that my priorities were somewhat arbitrarily chosen, and did not necessarily match the priorities of the physics teaching community. In full disclosure, when I gave the FCI to my students year after year I often found that my class wasn't transforming my students into Newtonian thinkers like I'd hoped it would... (My normalized FCI gains tended to be around 0.1 or 0.2, not nearly high enough to call my class a rousing success by this measure!) My class was successful in a lot of other ways, but through observing what other programs have chosen to do with their own physics first programs, I hope to learn more about what can be done most effectively. Hopefully, this blog can serve as a resource to others who are interested in doing the same.

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