Science

Bob and I began teaching the boys the Periodic Table two weeks ago. We started with electron configuration and moved into the reasons why the P.T. is organized the way it is. The guys seemed to enjoy it, especially with games like P.T. Bingo and Alien P.T. They really liked the logic questions. We tried to use lots of activities to keep them interested and by the end of the week they were doing quite well. Now we have moved into valence electrons, lewis dot formation, and bonding. Today I went over ionic, covalent, metallic and polar covalent bonds. They will need lots of practice with this, but I think I am definitely learning how to teach this a bit better. Hey, fourth times a charm.

Later this week we hope to do a lab testing the properties of ionic compounds vs. covalent molecules. Next week we are working towards a test on Chapters 5 and 6, right before the end of the term.

Since my last post we have covered the following topics in Environmental Science:
Evolution and Natural Selection
Primary and Secondary Succession, with special emphasis given to successional changes on Mount St. Helens
Symbiosis and Coevolution: mutualism, commensalism, parasitism (Watched a great video called “Living Together”–fantastic, a classic)
Predation: how to avoid predation and how to be a predator
Ecological Niche: Fundamental vs. Realized
Limiting Resources
Keystone species such as fig trees and top predators
Species Richness

The boys took a quiz on this material and we set up our Winogradsky Columns for our bacterial study. That seems to be going well. They are taking water quality tests each week and photographing the changes seen in each column. We will follow for the next five weeks.

Then, last week we tackled Biomes, both terrestrial and aquatic. The boys had to create tables to compare the climate, productivity, species type, limiting factors etc. for each terrestrial biome. I went over freshwater and salt water systems in class. They also had a quiz at the end of the week, which they thought was very hard. I have no finished grading it yet.

This week we are moving into Population Dynamics and Ecology (one of my favorite topics actually). We are going over:
Population density
Growth rate calculations
Environmental Resistance and Carrying Capacity
Log curves vs. exponential growth curves
Reproductive strategies: r-selected species vs. K-selected species
Survivorship curves
Density dependent vs. independent limiting factors
Predator-Prey relationships
Boom or Bust relationships
Thomas Malthus and predicting human population growth and carrying capacity
Demographics
Age structure diagrams of developed, developing and underdeveloped countries

Good stuff! They have calculations to do tomorrow and in our double period we are going to work on exponential growth and they will research Thomas Malthus’ ideas. I also have a lab for growing radishes to illustrate competition of resources, but that will have to wait until next week as they did not include enough radish seeds. It is always something.

It has been awhile as I have learned that I can only seem to access the blog from home, my office is a blogging black hole. Even Beaver tried and his whole computer practically froze. I blame the breaker switches and excessive number of electrical outlets (roughly 50). I am likely growing a nice, big brain tumor due to my time in the 8th Grade Dean’s office.

Since my last post we have covered the following topics, the kids are going to be tested on them on Wednesday:

Phases and phase changes
Gas Lawes (Boyles, Charles, Combined)
Atomic Theory (Democritus, Dalton, Thomson, Rutherford, Bohr and Electron Cloud)
Components of an atom
Atomic number, mass and isotopes
Energy shells, excited and ground state electrons

Once they get past this test (and Bowman and I are trying to make it challenging) we will come up with some fun capstone activities for Thursday and Friday. Then, next week, we are moving on to the Periodic Table and then bonding. Fun!

Students did a lab with agar cubes of different sizes to see why cells aren’t larger than they are (oxygen can’t diffuse to the middle fast enough).  I did a demo with eggs with shell removed with vinegar.  One was placed in distilled water and it gained weight due to osmosis and one placed in salty water lost weight.  We started a DNA unit on friday with a informational packet that had them answer questions and color the different parts of DNA.

Students prepared for and took a Cell Test.  Then students did a diffusion lab involving dialysis tubing that is permeable to iodine but not starch.  Iodine turns purple in the presence of starch so they can quickly see that only iodine diffuses across the selectively permeable membrane.  Next week they will do a lab involving different sized agar cubes and determine what limits cells from being larger than they are.

As we rounded out September we finished our unit on macromolecules.  We covered the basics of monomers and polymers and discussed carbohydrates, lipids, proteins, and nucleic acids in detail.  Woven in to these topics were the general ideas of isomers, and the relationship between a molecule’s structure and function.  The students had their first test which covered some basic chemistry and organic compounds (Campbell 7th Ed. Chapters 1-5 with a focus on chapter 5).

We have since started our unit on the cell and the cell membrane.  We have read chapter 6 from Campbell and discussed major types of cells, details of organelles, and cellular evolution (endosymbiotic theory). 

The students submitted their first formal lab on fermentation and we are now starting work from the lab manual and will do the osmosis/diffusion lab this week.

We had our first test on one- and two-dimensional kinematics.  The boys also designed their second laboratory: Measurement of Friction Coefficients.  We have started and almost completed Newton’s Laws.  We spent a lot of time of contact forces and friction.  We also introduced the role of integration in physics.  This was done via the exploration of air resistance in free-fall.  We solved the problem analytically and also introduced the concept of numerical integration.  A day was spent demonstrating how to integrate on an Excel spreadsheet.  Next week the boys will be assigned a problem exploring free fall and numerical integration.  They will also be required to perform one of the laboratories designed by their fellow students.  We will be exploring energy towards the end of the week.

This week in Lower School Science, properties were being observed in almost every class.

 Kindergarten observed the physical properties of shells, using their senses to ascertain size, texture, and color.  They then sorted the shells by appearance and created pictograms and bar graphs to quantify their results.

First grade finished their study of nutrition by making their own butter in test tubes.  After observing the properties of cream, the boys “shaked, rattled, and rolled” the cream (which they learned was a colloid) became a solid.

 Second grade continued learning about the properties of water.  After finishing their experiments on surface tension, the boys observed cohesion of water droplets by moving the droplets with air.  The water droplet race was a big hit, and reinforced cohesion.

 Third grade observed the properties of rocks by weighing, measuring, and recording color and texture.  The boys will begin using field guides to identify rock specimens this week. 

Fourth grade used probability to analyze the amount of water coverage of the earth.  By tossing an inflatable globe back and fourth 100 times, and recording the number of times their pointer finger landed on land vs. water, they derived at estimates of the coverage.  They will finish this activity next week.

Next week:

K - Fish Observations/Dissection (discovering physical adaptations)

1 - Intro to Five Senses - Sense of Smell (”Mystery Smells” and “Peppermint Beetle” activities)

2 - Water Cohesion: Water Drop Experiments

3 - Begin Field Guide Rock Research

4 - Finish Globe Toss Activity (using probability to estimate the Earth’s water coverage), Water Facts Game, and Landforms Powerpoint and Bingo

Sami

This past week, we carefully examined our class’ two leopard geckos, Echo and Narcissus.  We discussed their natural habitat and specific features.  The boys then navigated through an online taxonomic chart to find out what phylum, class, order, family, genus and species the geckos belong to.  We defined binomial nomenclature and discussed the practical benefit of classification.  The boys went on an internet “Scavenger Hunt” to identify the kingdom through species of some common scavengers.

Next week we will begin to transition to our study of evolution.  We will discuss the stunning level of Earth’s biodiversity, and the boys will develop hypotheses to explain how they think the various species developed.    We will define evolution and look at a brief history of the development of the theory.  We will introduce  and begin to discuss other important terms like adaptation, natural selection, and common descent in order to develop vocabulary for use throughout the unit.