Monday, September 25, 2017

Homeschool Biology: CK-12 Biology Chapter 1--The Tree of Life, and How to Run a Scientific Experiment

CK-12 Biology is the textbook that we're using for Honors Biology for the 6th and 8th grades. Chapter 1 of the book serves as an introduction both to biology and to the study of science, or a review of both for those who've studied biology and used the scientific method before. I treated this as a review, and so we busted through this chapter in one week (as compared to the THREE weeks that it's taken us to get through chapter 2!).

Both my 6th and 8th graders are expected to read the chapter independently, each on her own tablet, and to click through the links to watch the in-chapter videos. My 8th grader is expected to answer all of the end-of-section review questions in writing, but my 6th grader is only asked to review each section with an adult (she doesn't know this, but she answers those review questions verbally during our discussions). My 8th grader also takes the end-of-chapter test, although it's open-book, but my 6th grader does not.

Section 1.1, "Science and the Natural World," is an introduction to the field of science and methods of scientific investigation, with an emphasis on the Scientific Method. We studied the Scientific Method just last month, during our solar eclipse study, so rather than review it, per se, we looked at it in a little more depth. We watched the Khan Academy video on the Scientific Method--



--and then the witch trial scene from Monty Python, as a funny comparison/lesson on WHY we have a stated procedure for scientific inquiry:



My kids love nothing more than heckling someone else doing something incorrectly.

To practice the Scientific Method, I modified this "M&Ms in Different Temperatures" experiment. I won't buy foam plates, because I don't hate the planet, so instead I bought two identical white plates from Goodwill, for less than the price of a pack of foam plates, I assure you.

I had the kids center and trace various lids and other circular items on the plates, then measure the radius of each, right in Sharpie on the plates:

This technique worked well, except that the maximum spread of each candy during the experiment didn't reach the outer circles. I should have had the kids use a compass and draw circles to specific sizes, and there should have been smaller sizes drawn, and more of them.

I also should have purchased and prepared a third plate, so that we could have had a control, but instead Syd conducted the cold water experiment-- 

--while Will conducted the warm water experiment, with me as time keeper and each kid recording the results in her science notebook: 
See the spread of the candy coating? It eventually got as far as the third outer ring, and the experiment would have worked better with perhaps ten rings evenly spaced in that area.
 The kids compared the results of their experiments, then I challenged them to choose a different variable and repeat the experiment independently. Will chose to repeat her experiment using boiling water, and Syd chose to repeat her experiment using room-temperature vinegar:

This was my secret test to make sure that they understood how to choose a variable and conduct an experiment.

For Section 1.2, "Biology: The Study of Life," Syd is the only one who had supplemental work, as Will just took an entire intro to biology high school class at our local university this summer. Syd watched the "Six Kingdoms" video on BrainPOP, with the expectation that she'd take and pass the quiz on the video, and then played "Sortify: Tree of Life," also on BrainPOP. This little living vs. non-living activity that she and I did when she was six years old would have also fit into this chapter, but of course the book's definition of living vs. non-living was a little more sophisticated.

I really like Crash Course Kids, so as supplemental videos to this section we watched "Living Things Change"--



and "Classifying Organism":



And that's Chapter 1 of Honors Biology! Chapter 2 is already a LOT meatier--and a lot more fun!--and as lab-heavy as I'm making it, I can easily see this particular biology study carrying us well into next summer.

Ooh, and I'm buying us a new microscope this week--stay tuned!

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