Category Archives: technology

Computational Modeling with VPython

The second session I led at the DuPage County Science Institute was on Computational Modeling with VPython.

I tried to explain what computational modeling is and how it is more than just programming. I then encouraged teachers to use computational modeling in their classroom and shared why I think it improves student learning.

We used VPython and the physutils package.

We started with John Burk’s example. I then asked each teacher to modify the model in some way and observe the results.

I then presented several starting examples that I created for my AP Physics B class and shared how students built upon these examples to solve everything from homework problems to their projectile motion lab practicum.

I left lots of time for teachers to explore these starting examples and help each other and get help from me. I saw teachers unfamiliar with Python create some pretty cool models in very little time.

Here are the slides I used to introduce computational modeling:

Download (PDF, 4.05MB)

Here are the links to the resources that I displayed at the end of the session:

LoggerPro Graphing Tutorial

I lead a session at this year’s DuPage County Science Institute on LoggerPro for graphing (a.k.a. because life is too short to struggle with Excel). The intended audience were teachers not familiar with LoggerPro whose students would benefit from using it for graphical analysis.

I started with the basics: specifying names, short name, and units for the dependent and independent variables; titling the graph; setting the graph options. I showed how linear the fit uses the specified variables and units and how to specify measurement uncertainty and see its affect with error bars.

We then focused on using calculated columns to perform linearization manually and then using LoggerPro’s curve fit feature.

Near the end of the session, I demonstrated some of the more advanced graphing features of LoggerPro with examples from this year:

  • multiple data sets on the same axis
  • multiple y axes
  • examine and tangent tools
  • grouped graphs (position vs. time and velocity vs. time)
  • histograms

Here is the tutorial handout I provided:

Download (PDF, 46KB)

Greatest Benefit of Canvas

Last spring, I was part of our district’s pilot for an LMS. I became a fan of Canvas and was very pleased when we selected it as our district’s LMS.

I absolutely love Canvas’ ease of use. I use all the typical features like announcements, discussions, and file storage. More unique features like modules help my students find everything they need for each unit and pages allow me to easily share enrichment materials.

However, looking back at this first full semester with Canvas, I was surprised which feature had the greatest impact on student learning. It wasn’t any of the above. It was SpeedGrader. Specifically, the ease with which SpeedGrader enables me to provide rich feedback to students on their assignments. Sure, I provided feedback before Canvas by writing comments on lab reports, but it was time consuming (I write much slower than I type) and not always legible (my handwriting is poor). I always had more feedback to provide than what I took the time to write. SpeedGrader has changed all of this.

Here’s my workflow for AP Physics B. Students create an ePortfolio in Canvas that contains all of the labs for which they perform analysis and are assessed. I create an assignment in Canvas for each lab and they submit a link to their ePortfolio. (The ePortfolio part isn’t critical, you could create assignments and have students submit their work in any number of ways.) In SpeedGrader, I can view their ePortfolio in one pane while typing feedback in another. This feedback is what has had the greatest impact on student learning.


I don’t score labs by subtracting a bunch of points, I read them. For my AP class, they earn a score of 1-5 which is reported in the online grade book, but doesn’t show up anywhere in Canvas. In Canvas, I just mark the assignment as complete or incomplete. In Canvas, the focus is on learning; not grades. What students do get is my feedback which often starts a discussion about their lab. My feedback is usually questions of the type I would ask of them in person. Questions that help them make connections between different ideas, clarify a misunderstanding, or illustrate an inconsistency in their analysis. In addition, I can easily point out sections that are incomplete. Many students have their notifications configured so that they receive an email when I submit feedback and some respond back almost immediately.

The integrated discussions in SpeedGrader is a perfect example of the role that technology should play in education. Enhancing a sound educational practice (rich feedback and discussion) by making it more efficient and easier for all involved.

Four of my five classes submit all of their assignments in Canvas. Guess what that fifth class will start doing this semester?

Near-Space Ballooning County Institute Session

My colleague and I, who advise our school’s Physics Club, volunteered to share our our experiences over the past two years designing, launching, and retrieving near-space balloons. Last year’s balloon reached an altitude of over 100,000 feet and captured amazing photos, video, and temperature and radiation data. We discussed the technologies involved in near-space ballooning such as GPS receivers, microcontrollers, programmable cameras, and sensors. We also shared different approaches to designing near-space balloons that fit a variety of budgets. Finally, we discussed this year’s project in which younger students are designing and building experiments to be launched as part of this spring’s balloon launch.

The slides we presented are below as is our handout with links to various resources. This is a fantastic project for a group of students to tackle. If you decide to try to launch a balloon, please feel free to contact me.

Download (PDF, 7.85MB)

Download (PDF, 37KB)

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.

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.

From Digital Junk Drawer to Online Exploration for Students

I’m not sure how many people will be interested in this post describing the tools and process I use to transform the bits in my digital junk drawer into online explorations for my students. However, I notice more and more educators using Macs, and, for those who don’t, they may be able to generalize these ideas using their own tools.

I create a topic page in Schoology for every unit:

Topic page

This topic page contains a bunch of links at least somewhat related to the unit. Each topic page has categories for simulations, articles, videos, and projects to make. This topic page is from the first unit which is somewhat less focused than the others and, therefore, has subcategories as well. While some of this material will be referenced in class, most of it is just for students to explore and enjoy. When I introduce topic pages, I tell students that when they are procrastinating, they should click on these links rather than randomly browse the web.

Creating these topic pages takes very little effort because of the tools that I use.

Every time I encounter something that may be somewhat related to physics, or at least science, or maybe just education, I drop it in my digital junk drawer which is Yojimbo. To be more precise, I tag it as I drop it in Yojimbo. This is as simple as a clicking a button or hitting a keystroke in Safari or NetNewsWire and typing the tags. My tags are organized around the units that I teach, the main concepts that are covered, and the types of activities I perform as an educator. I keep a list of my tags in a text document that I can reference if I can’t remember which ones to use. My Yojimbo window looks like this:


Yes, I have over 4000 items in Yojimbo and most of them are related to education. Most of the time, I just keep tagging and adding items to Yojimbo. When we’re ready to start a new unit and its time to create or update the topic page, I use Yojimbo’s collections to organize the links that I want to feature:


It is easy to filter by tags in Yojimbo and sort by date. I review the new items that I’ve added since I last updated the topic page and drag them into these temporary collections corresponding to the topic page categories (the lessons/labs are for items that I want to incorporate into class rather than the topic page). Once I’ve reviewed all of the new items, I highlight all of the items in a category and use FastScripts to run an AppleScript that generates HTML for all the items:

tell application "Yojimbo"
    set urlList to "<ul>
    set selectedItems to the selection
    repeat with bookmarkItem in selectedItems
        if the class of bookmarkItem is bookmark item then
            set urlList to urlList & "  <li><a href=\"" & (location of bookmarkItem) & "\">" & (name of bookmarkItem) & "</a></li>
        end if
    end repeat

set urlList to urlList &amp; "&lt;/ul&gt;"
set the clipboard to urlList

end tell

The script copies the HTML to the clipboard so all I have to do is paste it into the page editor in Schoology.

While I’ve focused on using Yojimbo to make it easy to create these topic pages, this is just one example. When I or another teacher vaguely remembers something, I can usually find it in Yojimbo in a matter of seconds. While I love 1Password, Yojimbo keeps an encrypted record of all my passwords and serial numbers. I also encrypt weekly backups of my web-based grade book since I certainly don’t trust its security. Yojimbo can handle more than just bookmarks, I give it images, PDFs, and text notes referencing journal articles or books which aren’t available online.

And yes, if you are familiar with Now, Discover Your Strengths and are wondering, Input is one of mine.

Near-Space Balloon

The Physics Club at my school recently completed our second-annual near-space balloon launch and recovery. Our goal was to launch the balloon payload to over 100,000 feet. We planned to record pressure, temperature, and radiation data; test the effects of altitude on biological samples; capture photos and video; and, ideally, recover the payload! While we didn’t achieve every goal, the launch and recovery was a resounding success.

An alumni of the Physics Club worked with Ken Walczak from the Far Horizons project at Adler Planetarium last summer and suggested that we contact Ken. The students contacted and met with Ken on their own, set the goals for the project, and designed and constructed almost every element of the balloon. (Ken provided the pressure and radiation sensors, while I provided the Arduino and temperature data logger.)

This project was a good excuse for me to buy a new Arduio Uno and the Data Logger shield from Adafruit. The data logger shield was easy to assemble, simple to interface with via the Arduino, and convenient to retrieve the data due to the SD card storage.

Armed with our supplies, we met up with Ken in El Paso, Illinois (selected due to its launch-friendly park and sufficient distance from Lake Michigan). With his experience, Ken provided many tips as well as the 1000-gram balloon!

We inflated the balloon:

IMG 5196

… assembled the payload and connected it to the parachute and balloon:

IMG 5201

.. and the president of Physics Club let go! (That process took over two hours!)

100 0316

The camera captured a great arial view of El Paso, Illinois:

IMG 1477

… and quickly rose above the clouds:

IMG 1567

While not definitive, based on our data, we estimate that the payload reached at least 105,000 feet:

IMG 2109

… before the balloon popped and the payload fell to earth:

IMG 2325

We used a cell phone that sent GPS coordinate to a web site to track the balloon. Unfortunately, the cell phone stopped sending coordinates immediately after launch. As a result, we had no idea where the balloon was until the payload landed back on the ground, two hours and forty minutes after launch. Fortunately, it landed in a vacant lot in a subdivision relatively close to the predicated location. We were able to retrieve the payload, recover all the data, and be home for dinner.

We had some issues with the data logging. The pressure data wasn’t valid (we were having issues before even launching; so, we weren’t too surprised). Also, the Arduino got too cold when falling and some of our temperature data may be suspect. Regardless, the graphs of temperature vs. time correlated with radiation counts will provide some authentic data for our freshman earth science class next year:


Next year, we plan on replacing our cell phone-GPS tracking system with a GPS receiver connected to a APRS transmitter. We don’t like losing contact with the payload during launch. We also hope to invite our district’s middle schools to design experiments to include in the payload. The students also expressed interest in adding a camera facing upward to capture a new perspective.

If you are interested in launching your own near-space balloon, feel free to contact me and, while limited, I’ll share our experiences!

How My iPad Replaced My Laptop

I started the fall semester with the intention to see if my iPad could replace my laptop during the school day. In short, it has. How was this possible? Before I elaborate, I want to be clear that I have an iMac at home that I use all the time and there are days that I use my school-issued tablet due to limitations of the iPad.

Key Features

I’ve been surprised by several of the features that I most appreciate about the iPad.

The best is that it turns on instantly. It takes my school-issued tablet several minutes to boot. Even if I wake it from sleep, it fails to connect the the wireless as often as not and requires at least a reboot. While this is an appreciated feature for me, I’ve recently realized that this is a killer feature for iPads in the classroom. When a student pulls a laptop out of the cart, boots it, logs in, and then later, shuts it down, a substantial fraction of class is spent with these worthless tasks.

The iPad battery is fantastic. I never charge it at school; I just plug it in every night. My bag is light and now there’s more room for lab reports.

VGA output is a critical feature. I need to display a variety of media via an LCD projector in my classroom. VGA output is not a universal feature; it has to be supported by individual applications. I’m surprised by how many people are unaware that an iPad can project slides via an LCD projector.

Key Applications

I rely on a number of important applications on the iPad in order for it to replace my laptop. Just as importantly, I rely on a number of applications on my Mac that interface with my iPad.


My life is manageable because of Omnifocus. I’ve followed the Getting Things Done methodology or something similar for years and Omnifocus; which is synchronized between my Mac, iPhone, and iPad; is the best implementation of it. Without Omnifocus, the iPad wouldn’t even be an option.


Yojimbo is my digital junk drawer. All of my bookmarks, notes, receipts, etc. are stored and tagged in Yojimbo. I don’t often need to create new items on my iPad but I definitely need to search and access them.


I often have slides to display in class. I’ve used Keynote on my Mac for years. Keynote on the iPad pretty much displays whatever I create on my Mac. The latest version of Keynote supports the display of presenter notes on the iPad while displaying slides via the LCD. This is a key feature for me as it allows me to scroll through my lesson plans while a slide is being displayed.


I used to copy Keynote files between my Mac and my iPad via iTunes. This is a huge pain. I now use Dropbox to have practically all of my files accessible from my iPad. I wish the iWord apps on the iPad would integrate seamlessly with Dropbox. No, I don’t want to use


Each of my logins is unique and relatively secure. I rely on 1Password on my Mac to manage this and it syncs with 1Password on my iPad. The 1Password iPad browser doesn’t work as well as Safari for some sights, but it works well enough for me to take attendance without having to type my log in information in every period.

Other Apps

PCalc: I teach physics, PCalc is the best calculator.

iBooks: I don’t read many books on my iPad, but I reference a ton of PDFs.

YouTube and Videos: These apps support VGA output so I can share videos with my classes.


I still use my school-issued tablet when I want to demonstrate how to solve physics problems. I was given an Acase iPad stylus for Christmas. It works better for writing equations than the Pogo Sketch, but I wish it had a finer point. The best note taking application that I’ve found so far that supports VGA output is PenUltimate. However, I plan to try Note Taker HD soon. If you have any recommendations for another stylus or app that would be well suited for writing equations as well as drawing diagrams, please let me know!

There are many excellent physics simulations available (PhET and OpenSource Physics). However, they require either Flash or Java. I’m tempted to compile my own Java interpreter so I can at least run some of the simulations but I really have better things to do. Hopefully, someone figures out a solution that is compatible with Apple’s application requirements regarding interpreters.

I occasionally wish I could display something via an LCD projector in an app that doesn’t suport VGA output. It would be great if the iPad supported universal VGA output (without jailbreaking it). It would be even better if it supported wireless LCD projectors (like the Epson one in my room).


Overall, I’m quite pleased with my iPad at school. I find that the benefits outweigh the limitations and I can go find my school-issued tablet when needed. Rather than replacing my first generation Intel-based MacBook Pro this winter, I bought a 27″ iMac instead. The price of my iPad plus an iMac is less than a new MacBook Pro. In case you are wondering, I really like the 27″ screen.