Monthly Archives: December 2011

Mechanics Modeling Instruction Reflection

I just finished my second year of Modeling Instruction for mechanics in my regular physics class.

While I attended a mechanics modeling workshop a few years ago, I remember when I first decided to jump into modeling with both feet. I was looking at a problem involving electromagnetic induction that required use of the equation F = BIl. All students had to do was to find three numbers, one in units of tesla, one in amps, one in meters and multiply them together without any understanding of physics. This was reinforced when I saw students in the next question trying to solve for resistance using Ohm’s Law and plugging in a velocity instead of a voltage. Many of my students weren’t understanding physics, they were learning to match variables with units and plug-and-chug. Our curriculum was much wider than deep and I felt that I had to make a change.

Fortunately, my desire to change the emphasis of the curriculum coincided with a county-wide effort to define a core curriculum for physics. While it wasn’t easy, the team of physics teachers at my school agreed that we had to at least cover the core curriculum as defined by the county effort. This was the opportunity to reduce the breadth of the curriculum, focus on understanding and critical thinking, and use Modeling Instruction for mechanics.

I felt that the first year of Modeling Instruction was a huge improvement in terms of student understanding. This past semester was even better. While just one measure, FCI gains reinforce my beliefs. In 2009, the year before introducing Modeling Instruction, my students’ average FCI Gain was .33. In 2010, the first year of Modeling Instruction, it was .43. This year, the FCI gain was .47. While I don’t credit Modeling Instruction as the sole factor that produced these improvements in students’ conceptual understanding, it is probably the most significant. We also started standard-based assessment and reporting in 2010 and, hopefully, I’m improving as a teacher in other ways. For me, the most important confirmation that I was on the right path was that I couldn’t imagine going back to the way that I was teaching before.

The three most important changes that I made this year were: goalless problems, sequencing of units (CVPM, BFPM, CAPM, UBFPM, PMPM), and revised Modeling Worksheets based on the work of Kelly O’Shea, Mark Schober, and Matt Greenwolfe.

There is still plenty of room for improvement, however. Pacing was a big issue. We still have to finish mechanics in one semester. As a result of the time spent in other units, I really had to rush energy and momentum. While students could connect to many concepts in the momentum unit with previous models, energy was completely different. However, this experience had a silver lining in that it may provide hope for other teachers who want to adopt Modeling Instruction but are concerned that they won’t have time to cover their curriculum. I decided at the beginning of the semester that I would spend the time I felt was needed on each unit to develop the underlying skills of critical thinking, problem solving, and conceptual understanding. When I got near the end of the semester and had to fly through energy, I didn’t introduce it as another modeling unit. Instead, I presented it to the students as another representation of mechanics. I encouraged them to apply their critical thinking and problem solving skills to this different approach. I was pleasantly surprised when they did as well as previous years’ classes on the energy summative exam despite the incredible short amount of time we spend on the unit. I think this supports the idea that students versed in Modeling Instruction will have a strong foundation that will allow them to readily understand unfamiliar topics as well as, if not better, than students who covered those topics in a traditional fashion.

Whiteboarding continues to be an area that requires improvement. I made a couple of changes that improved the level of discourse among students. When whiteboarding labs, I either explicitly jigsawed the lab activities or guided groups to explore different areas such that each group had unique information to present to the class. This variety improved engagement and discussion. When whiteboarding problems, we played the mistake game on several occasions. This too increased engagement and discussion. However, I feel that I still have a long way to go to achieve the socratic dialog that I believe is possible.

Next fall, I will dramatically shorten the first unit which focuses on experimental design and analysis. I will probably still start with the bouncing ball lab but then immediately move onto the constant-velocity buggies. That should allow enough time to explore energy and momentum in a more reasonable time frame.

At least I feel like I’m on the right path.

Honors Physics Über Review Problem

Honestly, I never look forward to reviewing before exams. We have a dedicated review day at our school and I have never found it particularly engaging or effective for students. A few students have a list of specific questions to ask, and they benefit from the answers and discussions, but many do not.

This year, in Honors Physics, the calendar was such that we ended up having three days to review for the semester exam. My colleague had a great idea: create the Über Physics problem (also known as the problem that never ends). Our goal was to review every one of our twelve more-challenging standards. We brainstormed on a sequence of events that could be woven into a story. At the start of class, we introduced the story for that day and then left students to work through the problems with each other, ask questions about needed information, and check answers. The next day, we would summarize the previous day’s events, associated standards, and solutions before introducing the next “chapter” of the story. For the past three days, students were the most engaged during review that I have ever witnessed. They were interested in the story and excited by what the next “chapter” might bring. These problems were challenging which I believe also contributed to the interest.

Some simplifying assumptions were made but the students weren’t too critical. Unfortunately, I made a calculation error that affected the third day’s problems. When the error was corrected, the final coefficient of friction was ridiculous. I’ll have to adjust the story if I do this again next year.

While much of the story was conveyed verbally, I’ll share the rudimentary pictures that I drew and some of the specified variables. Each page corresponds to one day’s part of the story. The perspective of the diagram changes at times to show the necessary information. The answers are written in green or red and were provided one day after that part of the story was presented.

Uber Physics Review Problem

Something Has Replaced My iPad in My Bag

For the last year and a half, I’ve almost exclusively used an iPad as my computing device at school. I was pleasantly surprised that practically everything that I needed to do: email, web browsing, demonstrating how to solve problems, and playing videos; I could do on the iPad. I loved that the iPad turned on instantly, never needed to be plugged in during the day, and weighed almost nothing. At home, I still had a traditional computer, an iMac, which I used extensively in the evenings.

Lately, as I’ve been more and more busy, I’ve noticed that during the day, I would have to capture tasks and postpone their completion since I could not efficiently handle them on the iPad. (Perhaps, a future post on Getting Things Done is warranted to explain the methodology I use for task management.) My extracurricular activities are ramping up and they require me to complete a more diverse and spontaneous series of tasks during the day.

I finally decided to make a change. I purchased a MacBook Air and have been using it for the past week. It has been wonderful and I have been more productive. The MacBook Air has many of the characteristics of the iPad: near-instant on, incredibly light, and long battery life. In addition, I can do almost anything on the MacBook Air at school as I can do at home on the iMac.

I haven’t set up a new Mac in a while and I was surprised at how different my experience was with the MacBook Air. With the advent of Dropbox and iCloud, I didn’t copy any files when setting up the MacBook Air; these services synchronized, and continue to synchronize, my contacts, calendar entries, mail, photos, and files between my Macs and iOS devices. For the first time, when I pick up any of my computing devices, I feel that I am at home and not using a satellite computing device that is just a snapshot.

Not everything is perfect, however. The iWork Apps on Mac OS X, need better support for iCloud so that document management is round-trip between Mac OS X and iOS. I expect that this will be addressed, but, for now, I continue to use Dropbox and manually integrate changes made on iOS devices back to the Mac. Particularly annoying are the issues with the MacBook Air running Lion and wireless networks. I’ve hacked on my configuration enough to have a functional but annoying solution; so, I’m better off than some. Regardless, I’m amazed that Apple has yet to address these issues. Finally, the MacBook Air isn’t a tablet. I continue to use the iPad on its own when I want to demonstrate how to solve problems because I can write well on it with Note Taker HD, it projects well on the screen, and it is easy to export my notes to PDF files and post them to our class web site. Perhaps I’ll find an app that makes the iPad function as a drawing tablet for a MacBook.

I haven’t given up on the iPad by any means. I still hope to run an iPad pilot with my class. I think an iPad has several advantages when used in a classroom by students and teachers compared to traditional laptops and I want to explore these. Personally, I still use my iPad. I expect that when traveling or attending a conference, I will only bring my iPad. Finally, nothing is more immersive than curling up on the couch with a blanket and an iPad and reading.