Friday, January 1, 2016

Catching Up; Space Cycles - Day & Night

After we have studied the universe, I introduce my students to the idea that what happens in space can have a direct impact on our own planet.  Regular, predictable patterns in space produce regular, predictable patterns on Earth.

First we review rotation and revolution.  My students are pretty comfortable with the concepts so it is a quick review.  I use an interactive graphic organizer to reinforce the terms and move on.

Then we look at patterns in day and night.  
My students are aware that day-->night-->day-->night is a pattern.  They are also aware the the number of daylight hours is greater in the summer than in the winter.  Since my students tend to be well-traveled, most know that some places have daylight later into the evening than others, or that the sun sets earlier in some places than others.  They have all heard that sometimes the poles have nothing but day or nothing but night.  What they do not know is that these differences are very regular, very predictable.  They do not know the relationship of of latitude to the number of daylight hours.
We do an investigtion called "Days and Nights Around the World" in which the students graph the number of hours oh daylight at different latitudes This creates a pictures of very obvious patterns.  Graphing anything takes my students a long time.  
Graphing this data and identifying the patterns takes one full class period.

However, when we are finished with the activity, and the processing of the activity, students have a really good grasp of how the number of hours of daylight varys due to latitude and time of year.