Saturday, May 05, 2012

"Why Is There an Apple with a Knife Stuck in It in the Fridge?"

Husbands and fathers of homeschoolers have to put up with all kinds of weirdness. When we were staying with Steve in Kansas, he wondered why an apple with a knife stuck in it was in the refrigerator. I explained that we were modeling why seasons occur. Then, he asked why I had the string and tacks out. I told him I forgot to put them away after drawing an ellipse with a string. He had never heard of that before, so it was our turn to teach our resident engineer something new!

When we read science books, we don't just read them. Often we try to live them. Pamela and I were learning about the seasons and why they occur. I had a feeling that the diagram in the book and written explanation might not be enough to make it clear. I labeled an apple with the letter N for north pole and S for south pole. Then I drew a line representing the equator and labeled that. I stuck a knife in it to represent the polar axis.

Then, we took a piece of cardboard and practiced drawing circles and ellipses with a piece of string. We drew an ellipse on a big piece of cardboard, and I made four marks to represent the four seasons. I did not label them because that is what we were going to discover! We darkened the room, removed the lampshade, and placed the lamp in the middle of the ellipse. The plan was to tilt the apple, move it around the lamp in an elliptical orbit, and mark the seasons.

We did something similar to illustrate night and day way back when I homeschooled Pamela and David. David caught on immediately to the idea that day was where the light shined and night was in the shadow. Pamela could not make the connection at all but, at least, she learned that the earth spins. Last year, we revisited the day and night demonstration, and it clicked for Pamela. I suspected she might be ready to grasp the connection between the earth's orbit and seasons.

Her background knowledge played a role in how I structured this. Pamela, a savant in calendars, knows many facts about the calendar. She taught this to herself by researching it on Google.
  • A common year has 365 days.
  • A leap year has 366 days.
  • February 29 only occurs in a leap year.
  • Spring begins around March 20 or 21.
  • Summer begins around June 20 or 21.
  • Fall begins around September 22 or 23.
  • Spring begins around December 21 or 22.

Unlike most people I know, Pamela has an advantage: not only have we lived in Alaska where days are really long in the summer and nights are really long in the winter, we have visited family in two countries near the equator (El Salvador and Guatemala). We have also stayed in South America for nearly a month. In 2006, we left Carolina on a hot summer day before the equinox and arrived in Santiago, Chile on a chilly winter day. Three weeks later, we said adios to the spring blossoms of Chile and hello to the cooling fall temperatures of Carolina. Pamela saw for herself seasonal oddities that other children must be told. Life experiences have given her more facts.
  • When it is summer in North America, it is winter in South America (and vice versa).
  • When it is spring in North America, it is fall in South America (and vice versa).
  • Days are longer in summer, and shorter in winter, especially when you live closer to one of the poles.
  • Some countries never have snow (the ones near the equator).

Since she understood why we experience day and night last year, I had hope the seasons would make sense to her. First, we tried the day/night demonstration to tie into her prior understanding and she had no trouble pointing out to me which part of the apple had day and night. Then, I tilted the apple and began moving it along an elliptical orbit. I stopped at the location for summer in North America, and Pamela could easily see how the sun was shining very constantly on the North Pole while the South Pole was stayed in darkness. Because of her previous experience, she saw right away how it had to be summer in the northern hemisphere and winter in the southern. We marked that on the elliptical cardboard. We continued working through the seasons, and the next day Pamela copied the diagram from her book into her science journal.
After she drew her diagram, we spent the week reading about the seasons and their connection to the motion of the earth. We drove back to Carolina and read another chapter on the northern lights the following week. We studied the seasons three weeks ago and have not reviewed any of the material. I did not drill her on facts because that is not part of a Mason paradigm. The video is a short clip of what she narrated about the chapter on seasons. While the transcript does not look like much, you have to watch the video and see how she uses her hands to illustrate the orbit of the earth and demonstrate her clear understanding.
The earth was spinning from year. Days—about 365 and 366 days leap year and common year. Around Spring, Summer, Fall, Winter.

1 comment:

Mylinda said...

I bet she was thrilled to be able to teach someone else what she had learned. My kids learned best when they could teach it to someone else.