Speeding Cameras and Project Based Learning

This year I wanted to undertake Project Based Learning. I’ve attempted physics modeling the past couple years, and although it’s effective in many ways, I still feel there are more effective ways to engage my students and have them understand the concepts on a more “real life” basis (partially inspired by Dan Meyer’s blog post about authentic contexts). I figured I would try more authentic and engaging contexts, thus… projects. However, I found (and still find) PBL a bit intimidating because one of the keys of PBL is cross-curricular integration, and honestly, I wasn’t sure how physics integrated with the languages and humanities– at least authentically.

I don’t think I have a solution, but I may have found a starting point that at least gives me hope. Several weeks ago, I was inspired by an article about a man who fought several speeding tickets using basic physics (found on the Twitter/blogosphere).

“What a neat application!” I thought. Use pictures and time stamps to figure out how fast an object is moving. To solve for the speed of the truck, I needed more info on the truck, so who would know better than the man himself, Mr. Will Foreman (the accused). I found his e-mail address and sent him a message explaining who I am, what I was trying to do, and how he could help. His reply follows:


Yes, my company’s encounter with the speed cameras in the Town of Forest Heights Maryland could provide an interesting example for class. Sadly it might prove more valuable to a social studies, or civics class.

During my most recent visit to the courthouse I was contesting 15 citations. I was confident as the evidence was obvious and the law is quite clear. To my surprise, the evidence and the law didn’t matter. I experience first hand how our justice system “works” for the poor and uneducated. I was naive to think facts and the law matter. They do not. Money matters!

Judge Devlin treated me as though I had an extensive criminal record. I was guilty the moment I arrived in his court room. F. Lee Bailey could not have helped. I was threatened with contempt if I simply presented the photos from the citation. The same photos that are supposed to be the evidence against us. It was a very sad day.

I have been a victim of theft before. So-called customers and employees have stolen parts and cash. Never before have the perpetrators been in uniform or robes. That afternoon costs my company $937.50. It was a very sad day. I am appealing.

As far as the lengths of the vehicles, the red Ford Ranger is exactly 16 ft 6 in. Most garages are 20 ft deep. You can find the vehicle’s lengths on line with Wikipedia etc. Suffice it to say our delivery vehicles are between 16 – 18 ft.

Here is a link with some more photos. I put the distance required for validation.


Best of luck with your lesson.


Mr. Foreman’s reply helped me see a bigger picture. This is not just an application of physics, but it brings up the issue, “What role does science, math, and technology play in our legal/justice system? How can it be used to argue for against one’s innocence?” In trying to address the big issue on our mind, “So am I getting a ticket??”, Mr. Foreman’s reply also reminds me that this ties into issues beyond stating a case and backing it with evidence. The social issues become apparent. “If we can provide a persuasive argument using math and science, is that enough to make the changes we seek? How do we go about making social change? How do we become effective leaders???” The questions are endless! :oO I would have no idea how I would connect that to social studies, but I think it would at least create a good starting point for a conversation with a social studies, civics, leadership etc teacher.

I think situations like this help emphasize that much of what we do in math and science, especially in terms of problem-solving (word problems), are really tools we need for solving problems in a bigger picture (fighting a ticket, defending/prosecuting a suspect, making social change).


So… “What can you do with this?” At this point, my more concrete ideas are limited to physics applications. Some projects students can do regarding this context (refers to some resources, listed at the end of the post):

  • In my PowerPoint presentation, I show Mr. Foreman’s superimposed photo (sans attached data) and ask “Is it possible to calculate the speed of the car? If not, what else do we need to know?”. Let students brainstorm. More questions may pop up. “What’s that? Looks like we have more data here…” (next slide includes time data)

The media can be used as an assessment…

  • For a lower level analysis focusing on just the concept of constant velocity, present students with the speed camera photograph and give the prompt:
    “You are Mr. Foreman’s attorney. Use the photographic evidence to present a case to the judge, defending Mr. Foreman.”
    Remix: “The judge isn’t very well educated in math and science. (How does that change your presentation?)”
  • For higher level thinking, present them with the speed camera photograph, maybe the audio recording of the court hearing, and the information about the speed cameras from the manufacturer website, then give the prompt:
    “You are the judge. Based on the information and evidence available, do you think the accused is guilty beyond a reasonable doubt? Why? In your argument, show that you weighed information from both sides.”

As for my own implementation of this, I introduced the scenario, then connected it to motion maps (a rough sequence can be seen on my PowerPoint presentation, also embedded above). I felt the students were “hooked” by the proposed scenario. As I delved further into the “content” the next few days, the connection seemed to weaken as an interesting context turned into interpreting diagrams, graphing, plugging things into equations, etc. I’d like to connect back to this context somehow in my summative  assessment (a relative term, in SBG) of this unit (constant velocity). Meanwhile, I’m also doing the quintessential constant velocity buggy labs. So far there’s little sign the students see connections between the things in this unit, and only seem to focus on one activity at a time, isolating the things they learn. Perhaps I’ll have them reflect on how everything we do can be applied to the speeding camera situation so they can strengthen those common threads.


Reflections on My First Year of SBG

This is my first year trying SBG (Standards Based Grading) after being inspired by a handful of teachers. (ddmeyer, jybuell, ThinkThankThunk, fnoschese) I taught five sections of physics this year and have used “traditional” grading prior to this year. So how do I feel about the switch?…

The good

  • I felt more focused by creating objectives and prioritizing objectives instead of like in the past, where I just throw things at them and “hope it sticks”. 90% of it sticks? “A” for you! 70% of it sticks? Even if none of it was a core idea? “C” for you!
  • Students were relatively on-task for most activities, considering nothing was actually “worth points”. I was afraid the first assignment of the year would be met by a conversation like this:
    S: How much is this worth?
    T: um… your grade is determined by quizzes and tests
    S: … so, nothing?
    T: …
    S: [sits back and stares at ceiling]
    But that never happened. Sure, I had students who didn’t do diddly squat, but based on my prior experiences, I’d say these students would have done no more work than if assignments were worth points.
    At first it was a bit difficult not having the crutch of threatening students with loss of points, but this only encouraged me to make my activities more meaningful and engaging, and eventually it was overall liberating not feeling like I had to “motivate” my students by dangling the points carrot in their faces.

The bad

  • Students focused on objectives by their labels (T3, CV2, EM4, etc.). I’m not sure they ever read the actual objective. So in their heads they were trying to “learn CV2″ instead of “learn how to calculate the average velocity of an object”. Instead of learning what was described, they were learning “how to do those types of problems labeled CV2″.
  • Some or most students were motivated to remediate missed objectives, but it turned into a bunch of 1-on-1 tutoring sessions. I’ll need some way for them to remediate that’s not such a huge barrier that they would rather take the lower grade than relearn the material. Currently the only ways for them to remediate is to ask a friend (not a viable choice for everyone), ask me (takes up my time), or research on their own using the textbook or online resources (not going to happen). I’d like to create some accessible resources so if they do come to me for help, I can direct them to these resources. Or tell them if they’d like to re-assess, they must first offer evidence that they’ve gone over the resources.
  • Homework completion was still an issue, although it’s hard to say how much meaningful completion there was compared to when I had “traditional” grading. Second semester I tried a homework incentive system (complete/attempt more than 70% of assignments, +1 grade letter). No significant increase in number of students doing homework. Also, if they fell below 70%, it seemed like less incentive to do homework than before. I felt like since I started dangling the incentive system in front of their faces, this replaced any intrinsic motivation they might have had.
  • I’d like to have large and/or long-term assignments/projects. I think students can do short-term work in class (attempt a worksheet, whiteboard, do an activity) for no points, but I have serious doubts about students doing extended writing or any real “serious work” for no points.

Random notes

  • I started out with too many objectives each unit. I now try to combine them down to 6 for each unit/model so the list doesn’t seem daunting. I feel like long list lowers motivation (“so many things to learn!”).
  • I’ll keep the same formatting, which took a while to evolve into the current state. Objectives written at the top of each worksheet and assessment, and scores embedded in the objective list. (Another– although not great– reason for fewer objectives)


  • How do I assess projects and provide the proper motivation/incentives?
  • How do I assess students individually for projects?


I’ll never return to the old (traditional) grading system, which is relatively arbitrary and emphasizes points instead of learning. Although the “bad” list looks longer than the “good” list, the problems are less with the philosophy behind SBG, and more with my implementation of it this year. I will continue with the philosophy behind SBG, but I’ll need to adapt my implementation to how I plan to teach next year — with more projects, as activities and assessments (Project Based Learning is my next venture).

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