Mathematical models, flying disks, and flying rings

Laboratory 14 gathers data for a system for which the mathematical model is not known in advance. The students are to use their data to determine what mathematical form best describes the data. Desmos makes this possible.

Myreen, Ardy, Trevalouva
This term I borrowed the distance measuring technique from a statistics class exercise using paper aircraft. This worked surprisingly well. Early results from data suggest cleaner models from the static tape line. From a process standpoint the tape also worked better. In the past the recorder had to walk off the distance with a GPS. Using the static tape the recorder could remain downrange, recording data and returning the ring or disk. This was quicker, more efficient, and reduced the amount of back and forth walking a recorder had to do. Twenty throws could generate 800+ meters of back and forth walking for the GPS holder.

I spent more time this term both demonstrating and laying out the mathematical argument that non-flying objects l…

Invasive species walk and talk

With partly cloudy to overcast skies overhead and relatively dry ground conditions, the invasive species walk and talk went well. The class began outside under the Terminalia catappa tree with a brief report on student engagement with Schoology, the learning management system used by the course, and handout on the material culture essay.

Terminalia catappa starting point behind Kiyoe, May-me, Reinhardt, Megan Ruth, and Shanaleen
I then handed out information on the "six steps to extinction" as outlined in a study by Paul Downey and David Richardson:

"They identified six thresholds along the extinction trajectory of plant species affected by invasive plants.

Plants die quicker than they can be replaced by their offspring in some locations.Plants disappear from some locations entirely, but potential offspring remain as'propagules', seeds or spores that could regenerate a new cohort of individuals.Some locations lose both individual plants and their propagules. With…

Floral litmus solutions

In physical science laboratory thirteen the students use floral litmus solutions to determine whether household substances are acids, bases, or neutral.

Jayleen Alex, Trevalouva, Redsea working on the unknowns
The students bring in flowers. I do not provide guidance as to which flowers to bring in, there is no simple predictor for which flowers will work in any given term or at a particular time of day. Some flowers work better latter in the day (Hibiscus tiliaceus) while others work some terms and other terms do not work (Sphagneticola trilobata). Spathoglottis plicata tends to be reliable if freshly picked. And some flowers do not produce any pigment (Ixora casei, Saraca asoka. If boiled long enough, I. casei produces a light pink solution which can only detect bases.).

Johsper working with two flowers: one that detects bases, one that color changes with acids
Each floral litmus solution is first tests against a known acid (local lime fruit, karer tik this term) and a known base (ba…

Fruit types poster session

This activity worked well enough fall 2016 and then did not work well spring 2017 when students failed to bring fruit and what fruit they brought was only those available on campus. This term I challenged the students to bring a fruit unusual enough that I would not also bring the fruit.

I gathered fruit from the refrigerator, yard, Ellen's market, Saimon's market, and the campus. I spent $13 at Ellen's, gave a chap fifty cents for a Dois mango, and spent a couple more bucks at Saimon's. I wound up with cucumber, soursop (the only aggregate fruit today), noni (a nice multiple fruit), lemon, watermelon, banana, a Gala apple, Averrhoa bilimbi, guava, key lime, papaya, orange bell pepper, a coconut, seaside almond (dipwopw), among other odd ends that now escape my mind. I would eventually settle on a scale of 5/5 for a student having a fruit that I did not, 4/5 for having a fruit that I brought, and 3/5 for at least showing up and working on the poster session even withou…


While week twelve's electrical laboratory remains high on my list of laboratories in need of a refresh, I have not yet stumbled upon a laboratory that well keeps with the spirit of using only locally available inputs. Even as configured the inputs are not available on island.

Elisa tests her ring for conductivity
Elymore explores Ohm's law
Myreen and Trevalouva investigate Ohm's law
Elymore works on getting an electric motor than uses magnets to run
Elymore tries to get the electromagnet variation running, successfully
The Ohm's law data was very linear
Melsina and her child
Austin and Justice working out the voltage
Amy-lang tests materials for conductivity