I decided this year to write a 180 blog, which has put this blog into a state of dormancy (is that even a word?) I didn’t expect. First off, my 180 posts are longer than they probably should be, so they simply take longer to write. Also, I do most of my interesting reflection over there. Here are a few ideas I’ve been kicking around the last week:

1. Our projects should be a reflection of what we learn in class.

I’ve run a musical instruments project as well as a pinhole camera project this semester.

For the musical instruments, kids struggled to see how placing frets on a stringed instrument was an application of our string resonance relationship. Next year, I want to have a lab where we build a monochord (single string instrument) complete with a full octave of frets. This’d hand off to the full project very smoothly.

For pinhole cameras, I will modify to ask for them to calculate the magnification based on object distance and image distance. Then I’ll ask them to predict image height based on magnification.

Do you do projects? How do you keep them closely aligned to the rest of class?

2. Labs are fun to do but my current format is a PITA to grade.

Lab writeups take me over a week to grade. I don’t see that changing. A week is too long for a student to actually use the feedback. How can I create a self-checking lab? Ideally, once a paper is handed in, it’d already be corrected.

I’ve done a little of this — some labs have a section I have to sign off on before the kids move on. When grading, I just look for my initials. Maybe my grading solution is as simple as building similar checkpoints throughout all my labs.

3. How might I better develop units-sense in my freshmen?

What I mean is “how can I get the kids to see that units matter?” If you say you need a pinhole diameter of 0.6, I have no idea how big that is because you didn’t tell me inches or millimeters (it was millimeters). My kids view units in physics like they view showing their work in math — busy work the teacher makes you do that’s just picky details, not actually useful.

I can absolutely see incorporating units into projects in a way that makes them useful. Sometimes I have to control the power tools and the kids have to specify the size of a cut. If a kid doesn’t supply units, I can purposely choose the wrong units. A board that should be 2 inches wide could be made 2 meters wide, for instance. How do you drive home the value of units?