Monthly Archives: October 2011

ISEC 2011: Standards-Based Grading for High School Physics

This post is to capture the resources discussed in the Standards-Based Grading for High School Physics presentation (P154) at the Illinois Science Education Conference. Mark Rowzee and I presented our experience in adapting standards-based assessment and reporting to two different physics courses over the past three years. Our abstract is:

We will share our experience in implementing standards-based grading (a.k.a. standards based assessment and reporting) in our regular and honors physics classes over the past two years. This methodology has helped students focus on learning and understanding and not collecting points for a grade. It has helped us focus on defining meaningful standards and providing helpful feedback.

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Links to Resources:

General Physics Standards

This is a follow-up post to the Honors Physics Standards post that enumerates the standards that we have defined for our General Physics class. As I mentioned previously, this year, our entire school is replacing the traditional report card with a standards-based report card. The standards reflected on this report card, which we call report-card standards, represent an aggregation of several of the more-specific standards and are common across both high schools in our district. For General Physics, we have defined the following report-card standards for the whole year.

Report-Card Standards

  • science as a process
  • understand the basic concepts of kinematics
  • understand, explain, discuss, and apply Newton’s Laws
  • understand the basic concepts of energy and energy conservation
  • understand the basic concepts of momentum and its conservation
  • explain, discuss, and calculate the properties of electrostatics
  • explain, discuss, and calculate the properties of electric circuits
  • understand, explain, and discuss the properties of magnetism
  • describe wave type, properties, and interactions
  • understand the relationships among science, technology, and society in historical and contemporary contexts

Below are the more-specific standards that we use for General Physics during the fall semester. These standards are influenced by objectives defined by a group of physics teachers working together at the county level as well as Modeling Instruction.

Fall Semester Standards

STT 1. I can build a qualitative model, identify and classify variables, and make tentative qualitative predictions about the relationship between variables.

STT 2. I can select appropriate measuring devices, consider accuracy of measuring devices, maximize range of data, and calculate error propagation for an experiment.

STT 3. I can develop linear relationships and relate mathematical and graphical expressions.

STT Lab 1. I can create and populate data tables for an experiment.

STT Lab 2. I can measure phenomena in the laboratory with minimum error.

STT Lab 3. I can create graphs from data measured in an experiment.

STT Lab 4. I can analyze graphs of data measured in an experiment.

STT Lab 5. I can analyze uncertainty in an experiment.

STT Lab 6. I can write a complete formal experiment report according to the specified format.

CVPM 1. I can distinguish between scalar and vector quantities.

CVPM 2. I can describe and analyze constant-velocity motion based on graphs, numeric data, words, and diagrams.

BFPM 1. I can draw a free body diagram and add vectors graphically to find net force.

BFPM 2. I can identify the Law of Inertia (Newton’s 1st Law) to various situations in the real world.

BFPM 3. I can identify action-reaction force pairs (Newton’s 3rd Law) and the fact that they act on two separate bodies.

CAPM 1. I can describe and analyze uniform-acceleration motion based on graphs, numeric data, words, and diagrams.

CAPM 2. I can apply the various kinematics equations in one dimension.

UBFPM 1. I can draw a free body diagram and use the concept of net force to solve problems using Newton’s 2nd Law

UBFPM 2. I can identify how different factors affect the force of friction and can differentiate between static and kinetic friction.

UBFPM 3. I can solve problems using the coefficient of friction.

UBFPM Lab 1. I can determine the relationship between force, mass, and acceleration using experimental data.

PMPM 1. I can justify that if the only force acting on an object is gravity, it will have the same constant downward acceleration regardless of mass, velocity or position.

PMPM 2. I can apply the various kinematics equations in two dimensions while recognizing the independence of horizontal and vertical variables.

PMPM Lab 1. Model the path of a projectile based on experimental data and use this model to hit the predicted location.

PMPM Lab 2. Compare predicted values based on a model against experimental results.

COEM 1. I can identify that energy is transferred and solve problems using conservation of mechanical energy (kinetic energy and gravitational potential energy)

COEM 2. I can identify work as a change in energy and calculate its based on force and displacement.

COEM 3. I can analyze the rate of energy change of a system in terms of power.

COEM Lab 1: Perform an experiment to compare the loss of gravitational potential energy and the gain of kinetic energy of an object moving down an  incline in order to calculate the energy transferred between the system and the environment.

COMM 1. I can identify momentum of an object as the product of mass and velocity and relate the change in momentum (Impulse) to the force acting on it over a period of time.

COMM 2. I can analyze the momentum of a system of objects in one dimension and distinguish between elastic and inelastic collisions

COMM 3. I can solve problems using conservation of momentum were the net external force is zero.

Spring Semester Standards

ES 1. I can identify the charge on each sub-atomic particle and describe the behavior that each has on each other and how these particles move in a conductor.

ES 2. I can apply the principle of conservation of charge (charge is neither created nor destroyed just transferred from one object to another) to predict the movement of charges in insulators and conductors.

ES 3. I can predict attraction and repulsion between charged and neutral objects and predict how charges will redistribute based on charging by contact and induction.

ES 4. I can apply Coulomb’s Law to two charged particles.

ES 5. I can describe an electric field and identify the electric field diagrams for a one or two charge system and identify the direction of the force experienced by a charge in an electric field.

ES Lab 01. I can predict the charge on a neutral object knowing the process by which it was charged.

ES Lab 02. I can demonstrate how to put a charge on a conductor using the processes of conduction and induction.

CIR 1. I can recognize and analyze series and parallel circuits.

CIR 2. I can apply how energy is conserved within a circuit (Loop rule) and how charge is conserved within a circuit (Junction Rule)

CIR 3. I can calculate equivalent resistance and apply Ohm’s Law.

CIR 4. I can calculate the power used by an electronic device.

CIR Lab 1: I can measure voltage and current with an appropriate meter.

CIR Lab 2: I can draw a circuit diagram and build it correctly based on a description.

CIR Lab 3: I can draw a circuit diagram for a circuit based on bulb brightness and observations of the circuit.

EM 1. I can recognize and explain what causes magnetic fields.

EM 2. I can identify the direction of magnetic fields.

EM 3. I can distinguish between magnetic fields and electric fields.

EM Lab 1. I can understand the relationship between magnetic and electric fields.

EM Lab 2. I can recognize that an object must be charged and moving in a magnetic field in order to experience a magnetic force.

WA 1. Know and identify the following features of a wave: amplitude, wavelength, frequency, crest, trough, node, antinode, and period.

WA 2. Identify, and compare and contrast, the two types of waves and how they transfer energy.

WA 3. Apply the principle of superposition to explain constructive and destructive interference of waves.

WA 4. Conceptually and mathematically describe reflection and refraction of waves.

WA 5. Conceptually and mathematically demonstrate the relationship between velocity, frequency, and wavelength for a wave, and how wave medium affects these variables.

Understand the relationships among science, technology, and society in historical and contemporary contexts.

The Danger of Misapplying Powerful Tools

When I was a software engineer, I frequently used powerful tools such as C++ and techniques such as object-oriented analysis and design to implement software that performed complex operations in an efficient and effective manner. I also spent a lot of time sharing these with others. However, I learned to provide a caveat: if misapplied, these tools and techniques can result in a much more significant problem than would result when applying less powerful ones. That is, if you are not skilled in the deployment of these tools and techniques, the risk is much larger than the benefit.

Other engineers didn’t always appreciate this caveat. So, I would try to communicate with an analogy. You can build a desk with a saw, hammer, screwdriver, and drill. You can build a desk more efficiently using a table saw, drill press, and nail gun. If you make a mistake with the hammer, you may loose a fingernail. If you make a mistake with the table saw, you may loose a finger. If you are not adept at deploying the tools and techniques, maybe you should stick with the hand tools until you are.

In reality, the risk of misapplying these tools and techniques is more significant than the impact on the immediate project. The broader risk is that others who observe the troubled project associate the failure with the tools and techniques instead of the application of those tools and techniques. People get the impression, and share their impression, that “C++ and object-oriented analysis and design is a load of crap. Did you see what happened to project X?” Rarely do people, especially people not skilled with these tools and techniques, have the impression that the problem is the application of the tools and techniques rather than the tools and techniques themselves. This, in fact, is a much more serious risk that threatens future applications of the tools and techniques in a proficient manner due to their now tarnished reputation.

A series of articles and posts recently reminded me of my experience writing software and this analogy. I feel compelled to start with a disclaimer since this post has the potential to come across as arrogant, which is certainly not my intention. I have not performed any longitudinal studies that support my conclusions. My conclusions are based on few observations and my gut instinct. I tend to trust my gut instinct since it has served me well in the past. So, if you find this post arrogant, before you write me off, see if these ideas resonate with your experience.


Let’s start with Standards-Based Reporting and Assessment (SBAR) (a.k.a., Standards-Based Grading (SBG)). Last year, my school started adapting SBAR school-wide. SBAR is a powerful methodology that requires proficient deployment. It is not easy to adapt and effectively apply SBAR to a classroom in an effective way that resonates with parents, students, teachers, and administrators. Proper deployment requires a fundamental change in the teacher’s and students’ philosophy of learning. While the effect of a failed deployment on the individual classes is unfortunate, the larger problem is that teachers and parents attribute the problems to SBAR and not its application. It takes much less effort to convince a parent confused about SBAR of its value than it does to convince a parent livid about SBAR due to a poor experience in another class. At my school, one early SBAR adopter stopped referencing SBAR or SBG at all in his class to distance his methodology from the problematic applications. Fortunately, my school has pulled back a bit this year. This is the risk of mandating application of a powerful tool by those not proficient in its deployment. This is not a unique experience.

Two years ago, another teacher and I decided to try to apply SBAR to our Honors Physics class. We mitigated the risk by limiting deployment to six sections of a single class taught just by the two of us. We sent letters to parents, talked to parent groups, discussed the system with students during class. Only after gaining a year of experience, did we attempt to adapt SBAR to our General Physics class which contained ten sections and was taught by four different teachers. The risk of trying to deploy SBAR on this scale initially was too great given our proficiency.


Someone recently shared this New York Times article that questions the value of technology in the classroom. In general, a given piece of technology on its own isn’t effective or not effective. Whether technology is effective or not depends as much on its application as the technology itself. It depends on the teacher and the students and the class. Personally, I’ll stick with my $2 interactive whiteboards. This isn’t because SMART Boards are inherently ineffective. It is because they aren’t effective for me and my students given my classroom and my expertise. I expect there are teachers out there who use SMART Boards quite effectively. They are probably sick of hearing how they are a complete waste of money.

I hope to have a class set of iPads at some point this year. My school isn’t going to buy iPads for every student. Instead, we’ll put iPad in the hands of 25 General Physics students in my classroom and see what we can do together. Start small, reflect, adjust, expand.


I participated in a Modeling Instruction Physics workshop in the summer of 2008. I didn’t dare to really start modeling in my classroom until last fall. Why? I believed that the potential risk to my students due to a misapplication of the modeling methodology was tremendous. I decided that it was better for my students to learn what they could via more traditional instruction than what I foresaw as a potential disaster if I misapplied the deployment of modeling. Even more importantly, I was concerned that I could put Modeling Instruction at risk of never being adopted if my failed deployment was interpreted as a failure of Modeling Instruction itself. Only after more research, practice of Modeling Instruction techniques, and discussions with others, did I feel comfortable deploying Modeling in my class last fall. In an attempt to shield modeling from my potential deployment failures, this is the first year that I’ve associated the label “Modeling Instruction” to my class.

I used to be surprised at how adamantly some Modelers warned teachers not to do Modeling Instruction unless they had taken a workshop. I now believe they are worried about the same potential risk that I am. Modeling Instruction is a collection of powerful tools and techniques. Done well, by a skilled practitioner, Modeling Instruction can be incredibly effective. Applied ineffectively, Modeling Instruction can be a disaster and tarnish its reputation. I think students are better served by traditional instruction than by Modeling Instruction applied ineffectively. Traditional instruction may result in a lost fingernail. Ineffective modeling instruction may result in a lost finger. There, I said it. Disagree in the comments. Just don’t take that quote out of context.

While not directly related to modeling, I believe this recent article supports my conclusions. The problem isn’t that hands-on labs are ineffective, it is that ineffective deployment of hands-on labs is ineffective.


I don’t want my thoughts that I’ve shared here to paralyze you into inaction. Rather, I hope that I’ve encouraged you to make sure that you have sufficient expertise so you can apply your powerful tools and techniques in an effective manner. Your students will benefit and the reputation of these powerful tools and techniques will benefit as well.

How do you do this?

  • Attend professional development opportunities (e.g., Modeling Instruction Workshops) that increase your skill with these powerful tools and techniques.
  • Apply these powerful tools and techniques in a limited manner as you gain experience and expertise.
  • Participate on Twitter, start a blog, read a bunch of blogs, participate in online discussions (e.g., Global Physics Department), and subscribe to email lists to accelerate your knowledge of these powerful tools and techniques.
  • Observe skilled practitioners of these tools and techniques, find a coach to observe you, welcome feedback from everyone.

N3L Activity Stations

While the Newton’s 1st Law activities serve as a fun and short introduction, the Newton’s 3rd Law activities provide a shared experience that spans several classes. The activities that the students explore are selected to highlight the most common preconceptions that students have about Newton’s 3rd Law. I stress how important free-body diagrams are as a tool in their physics toolbox and that, once they are adept at drawing free-body diagrams and once they actually trust their free-body diagrams, they will be able to explain a number of counter-intuitive situations. I introduce these activities by stating that Newton’s 3rd Law is one of the most easily recited laws of physics and yet is least understood. Here are the activities:

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Sequential Spring Scales

Sequential Spring Scales

The spring scales are initially hidden under the coffee filters. Only after students make their prediction are the coffee filters removed. Most students do not predict that the spring scales will read 10 N. Some predict 5 N (the spring scales split the weight). Some predict 20 N (10 N each way adds up to 20 N). In addition to drawing the free-body diagrams, this scenario can be explored further by asking students to predict the reading on the scales if one of the weights is removed and the string is tied to a clamp instead.

Bathroom Scale

This station provides an important shared experience that we will refer back to when discussing the elevator problems later in the unit. This station also generates a number of excellent questions such as “would the scale work on the moon?” and “how could you measure mass on unknown planet?”

Twist on Tug-of-War


Students were very interested in this station this year since they were in the midst of Homecoming Week and inter-class tug-of-war competitions were being held. It may have been the first time free-body diagrams were used in the planning of the tug-of-war team’s strategy. The dynamics platform in the photo is a cart build from plywood and 2x4s with rollerblade wheels and has little friction. Most students claim that whoever wins the tug-of-war pulls harder on the rope than the person who loses. Only after drawing the free-body-digram and trusting it, do they realize this is not the case.

Medicine Ball Propulsion

Medicine Ball Propulsion

This is a fairly straight-forward station. I often wander by and ask the students exploring it why they don’t move backwards when playing catch under normal situations. I also check at this point and see if they are convinced that the force on the ball by them is equal to the force on them by the ball.

Computerized Force Comparison

This is the most important station in that it helps students truly appreciate Newton’s Third Law. I setup several of these stations to make sure that everyone has an opportunity to watch the graph in real-time as they pull on the force sensors. This is the standard Modeling activity for Newton’s 3rd Law. For students still struggling to accept Newton’s 3rd Law while working through this activity, I challenge them to find a way to pull on the two sensors such that the forces are not equal in magnitude and opposite in direction. This activity also counters the misconception promoted by some textbooks (perhaps unintentionally) that the “reaction” force follows the “action” force. Students can clearly see that both forces occur at the same time. (We refer to paired forces according to Newton’s 3rd Law, not action-reaction forces.)

WALL-E and the Fire Extinguisher

Who doesn’t love WALL-E? I repeatedly loop through a clip from the WALL-E trailer. In addition to the questions on the handout, I ask students what is incorrect about the physics in the scene. This year, I also showed students this clip that Physics Club filmed several weeks ago:

N1L Activity Stations

I like to introduce Newton’s First Law with a series of activity stations for students to explore followed by a couple of demos. They have fun and it provides shared experiences which we can refer back to later. Here is the activity sheet that guides them:

Download (PDF, 32KB)

Many of these stations and demos have as much to do with impulse as they do with Newton’s First Law. I mention this and we revisit these stations and demos later when studying impulse.

Most of these stations and demos are fairly self explanatory. However, a few can benefit from a photo. Here is the “Nuts about Hoops & Bottles” station:

nuts, hoop, bottle

You quickly grab the hoop with a fast, horizontal motion. This station can become overcrowded because some students obsess over trying to capture the most nuts in the bottle. (I’ve seen students catch over twenty.)

The “Hitting the Stake” station is perhaps the most surprising to students. It is easy to build and looks like this:

hitting the stake

The “Spin the Human” station works best on teachers with little hair. We have one constructed from pool balls. This one is built with golf balls and a coat hanger:

spin the human

It is best to put the “Chopping Blocks” station in the corner. Some students have an incredible amount of aggression to release.

I’m sure everyone has seen the “Clearing the Table” demo. If not, MythBusters has an extreme version.

A couple of years ago, I captured the “Egg Drop Soup” demo with the high-speed camera. I usually have all four eggs make it.

What is interesting about these activities is the evolution of this lesson. When I started teaching, these were all demos. I put on the show and the students’ engagement was that they laughed. A few years ago, my team transitioned these from demos to activities. More fun, more engaging. Based on a suggestion from my instructional coordinator, I now introduce each station and have the students record their predictions before get up and start visiting stations. This ensures they actually make predictions since many of these stations are too enticing for them to make predictions before playing with them.

Maybe I’ll let students “Clear the Table” next year.