Sunday, August 11, 2019

Syllabus alternatives

In the last few years I've tried to reflect more on why I do certain things and what the students get out of each. Starting my 14th year I now have way more resources than I can fit in a year and can pick and choose what I want. I am making myself justify each activity, and "because we always have," doesn't cut it. At the start of the year one year I thought about my class syllabus and what I expected students to get out of it versus what my students actually did. I saw it as an important resource of information, a contract between us about how the class would be run with each of us holding up our part of it. My students, and arguably the adults in their lives, saw it as a box to check by signing it without reading it. Students would ask me all year questions that could be answered by reading the syllabus, I would find the copies they were supposed to keep all year on the floor in the first few weeks. So my syllabus was not being read, so it was not working as it was. So I changed it, two different ways for two different classes.

First, I changed my Physics syllabus from two pages of text into a visual syllabus (like an infographic). I loved the one page result that I made using Adobe Photoshop, even printed in black and white students found it much easier to digest.
A few friends wanted their own versions (above left) but I had to edit it for them because they didn't have the software.  This year I rebuilt it in powerpoint (above right) for my Conceptual Physics which makes it much easier to share. It's available here as a pdf so you can see how it turns out and a powerpoint file so you can edit it if you want.

For creating your own I have a few suggestions:
- Use pictures to represent what you can like the book cover and the calculator near the top.
- If you can represent it in a graph, do it!
- Be brief! Try highlighting the important words in your syllabus and see what little is left.

This version is still a paper, that requires a signature and should be kept all year. I retained this part of the traditional approach for my Conceptual Physics students because they will have a notebook in which they keep all their class materials and it will be glued in. For regular physics, as they are older, I will probably not do a printed version again.

When I began teaching AP Physics C and had to draft a new syllabus I again focused on what I needed and why. I wanted my students to read my syllabus as their was important information about the outline of the course. I wanted them to have access to the syllabus to read later but they did not have to necessarily keep the paper. So I decided to make a Google form that had paragraphs from my syllabus interspersed with comprehension questions for my students to answer. I made a similar version for parents with fewer questions and aligned more to things that might concern them more (like the A-/B+ border). The full text version of the syllabus is also posted on Google classroom so my students can access it anytime.

This will be my third year using the digital syllabus in AP and I love it. The students complete it sooner (I can even email it to them the weekend before school starts) and it takes care of a lot of questions because they actually ready it. When our school is completely one-to-one I will probably do a digital syllabus for all my classes but will probably use images like the visual syllabus instead of paragraphs in between.

Friday, August 09, 2019

The evolution of color vision in tetrachromats

Many of us have a sense of color-mixing among trichromats. There's this classic image of the primary and secondary colors of light achieved by overlapping monochromatic circles of primary colors.

We overlap the red, green, and blue in a triangle to produce magenta (red + blue), cyan (blue + green), yellow (green + red), and white (red + blue + green). We have three distinct cone receptors in our retinas, sensitive to red, green, and blue. So this all makes good sense.

But birds have four cones and can seen into the ultraviolet. Researchers say this gives them an additional dimension of color vision. Imagine red + ultraviolet. You can't: we don't have a name for that mixture, nor can we visualize it. A color mix square would be called for. Actually, that wouldn't work.

Seems the number of possible color-mixing outcomes is 2^n – 1, where n is the number of primary colors. Three primary colors yields 2^3 – 1 = 7 outcomes (R, G, B, M, C, Y, W). Then four primary colors produces 15 outcomes. But the color mixing square can only accommodate 13. How unfortunate. Downright unlucky!

Here's what I got when I tried to populate the cells of a color mixing square. D-oh! Now I'm getting why an extra dimension of color is called for here.

For many more details and implications, check out the Science Friday segment below.



When I say I'm a big fan of SciFri and appreciate the science communication work that host Ira Flatow does, you might suspect a "but" is sure to follow. Who am I to disappoint?

Listen again to the minute from 13:15 to 14:15. I cringed when I heard this over the air the first time through. Ladies, has this ever happened to you? Maybe it was the result of multitasking on Ira's part, but I'm reticent to make excuses for him here. In any case: awkward. The guests maintained composure, so good for them. Still though... I hope I'm never that guy (but I probably have been).