Chris Etapa [Gunsaulas Academy] Greenhouses on the
This is another activity that is part of the greenhouse project that Chris had talked about earlier in the year. Chris brought potting soil, which we moistened and which we used to fill 1 quart Ziploc™ bags. The soil was packed into the corners (to help the bag stand up) up to near the top of the bag (but leaving enough room for the bag to close). We sprinkled about 5- 6 seeds (we used pickling cucumbers) on top and sealed the bag. Put in a sunny window and let the seeds sprout until they are pushing against the top of the bag. Then open the bags and let the plants grow further until they can be transplanted. Each child's name and other information can be easily recorded on the bag. This activity is appropriate for many grade levels, with experiments (vary light, temperature, etc.) added and discussions made more sophisticated as the grade level increases. Wonderful, Chris! Thanks.
[Steinmetz HS] Boyle's Law
Walter had a large syringe (with a plunger that could be used to adjust the volume of air in the syringe) attached to a pressure gauge by a tube (and the entire system sealed) and mounted on a clear plastic mounting so that we could lay it flat on an overhead projector, and project it on the screen. Walter then reminded us of Boyle's law PV = nRT (Pressure ´ Volume = number of moles of gas ´ gas constant ´ Temperature), so that at constant temperature for a given number of moles of gas, P ´ V = K, a constant (at least for modest pressures, where, for example, attractive forces between closely packed molecules do not come into play). This also means that P =K / V.
As we adjusted the plunger we obtained the data given below:
|P ´ V|
Plotting the data as Pressure versus Volume, we obtained a (concave) curve that corresponded to P = K / V. The Gas Law works! Thanks, Walter!
Ed Scanlon [Morgan Park HS]
Ed asked for our help with this project, which is for his students in Earth Science. Ed provided students with an outline of each of three chapters. Ed wanted the students to write a paragraph summarizing the main focus of the chapter. In addition, Ed asked the students to find an article (in the newspaper, within the last year) appropriate to each chapter, and write a five paragraph essay about the article. Then Ed asked each student to design and describe an experiment to test some topic in each chapter. Finally, Ed asked them to write a summary of their work. All their work would be handed in as a "scrapbook." Three of Ed's classes did an awful job with this assignment. So Ed is looking for our counsel on how he might alter the assignment to increase the compliance rate without watering down the assignment. Here is what we came up with:
Notes prepared by Benjamin Stark.