Friday, January 9, 2009

The Clinometer Activity

So, you've taught altitude and azimuth. Your students have made their Clinometers. They know how to use them.

What next? You're ready to start your school-year-long observation activity!

Here's a good first day introduction:
  1. Beforehand, you should have drawn or taped long north-south lines in your parking lot/playground. This makes using the compass rose easier and is a good way to keep your students semi-under control! They tend to stay near the lines. If you are very lucky, your parking lot has natural North-South lines and you can convince the teachers to leave one area free all year. I didn't have that luck so drew my own with heavy tape.
  2. Before you take your students outside, it's a good idea to cover the rules and consequences. I always told my students that the first time was a test. Mainly, they must be very quiet in the hall on the way outside. As soon as they are outside, they must walk directly to the north-south line and get set up and take their measurements. No delays! Take and record both measurements. Line up at a certain spot when you are done. You have a total of 5 (or whatever) minutes to take the measurements and be lined up to go back inside. Consequences were, they didn't go outside the next day, but sat out in the hall by a neighboring teacher and waited for us to return. Worked pretty well for me. I certainly had my share of "hall sitters" over the years! They want to go outside, so they clean up their act quickly! REPEAT A CAUTION TO NOT LOOK DIRECTLY AT THE SUN!
  3. If you have to lock your door--I always did--then you are at the end of the line. You could tell them before you left that by the time you get outside, they should ALL be at work taking their measurements.
  4. Walk around with a clipboard with a list of names. I usually had them groups by teams, if I was using teams. There are a certain amount of Behavior Points that go on the Weekly Points that are unrelated to the grade for this activity. Another good management trick! Record points for good participation, etc. You may have to help a few of the groups. They may need reminders as to proper use of the rose or clinometer.
  5. Once all are lined up, remind them about being quiet in the hall and head back in.
  6. Once they are all back in and seated, tell them that from now on, they get to come in and record their readings on the chalkboard, whiteboard, etc. Perhaps each group has a different person record each day.
  7. HERE'S THE FUN PART. You have gone to this sight earlier and actually know what their measurements should be! Once you have all of the numbers up on a chart, have a volunteer take the average of each. Tell them how close the average is to the "real" azimuth and altitude. If you have "crafty" ones who check on the "real" numbers at home on the computer, this is why you walk around a lot outside to observe if they are all taking measurements. I never had any do this that I could tell.
  8. Have someone record the class average on the class data table. Each team records their own measurements on their labsheet. There are places for each class you teach during the day so you end up with a good bunch of hours of measurements by the end of the week.
  9. At the end of the week, they will make a graph of one day's data. Have them project the lines to the horizon at each end, for sunrise and sunset using dashed lines.

Some of the concepts learned early on:

  1. The curved line they graph on Friday shows the sunrise, sunset, and sun in sky for one day.
  2. The sunrise is almost NEVER at east, nor sunset at west. This is a BIG surprise to them!
  3. Once you get a few of them, have them compare two graphs at least one month apart. They will see the arc rising or falling at the highest point, depending if it's moving toward summer or winter.
  4. The length of the line corresponds to the length of daylight.

Very powerful stuff!

FUN LINKS: Click here for Weekly LabSheet for this year-long activity.
Click here for a good Azimuth & Altitude Worksheet.
Click here for a good Azimuth & Altitude Quiz.

IMPORTANT NOTE: You eventually want your students to get tired of using two instruments. You want them to eventually figure out how to combine the rose and the clinometer! Don't tell them this the first week! Keep your ears open and point out comments that relate to this without too much hinting to the solution. But after a couple of weeks, you're going to want to take a day and have them design and construct a new instrument, combining the two into one. Much easier to use! Also nice way to avoid them looking at the sun, because the little sun spot shines down on the compass rose.

Wednesday, January 7, 2009

The Importance of One Activity to Teaching Astronomy

Looking back on my 30 year teaching career, this one lesson is most representative of my teaching philosophy. Hands-on, active, meaningful learning.

The bottom line is this: by measuring the azimuth and altitude of the sun for the entire school year, you have set up many wonderful learning objectives.

Here are a few:
  1. Making scientific instruments
  2. Learning to calibrate and properly use same
  3. Taking accurate measurements over time
  4. Make qualitative observations using the five senses
  5. Collaborating with teams to work on a long-term project
  6. Recording and interpreting data
  7. Relate units of time (i.e., day, month, year) to the regular and predictable motion of the planets and moons and their positions in the Solar system
  8. Illustrate and explain a year as the time it takes a planet to revolve around the Sun
  9. Explain seasonal phenomena (i.e., weather, length of day, temperature, intensity of sunlight) as a consequence of a planet’s axial tilt as it rotates and a planet’s orbital position as it revolves around the Sun
  10. Predict the moon rise/set times, and eclipses when given the relative positions of the moon, planet, and Sun
  11. Relate changes in the length and position of a shadow to the time of day and apparent position of the Sun in the sky, as determined by Earth’s rotation
  12. Describe the pattern that can be observed in the changes in number of hours of visible sunlight, and the time and location of sunrise and sunset, throughout the year
  13. Recognize, in the Northern Hemisphere, the Sun appears lower in the sky during the winter and higher in the sky during the summer
  14. Recognize, in winter, the Sun appears to rise in the Southeast and set in the Southwest, accounting for a relatively short day length, and, in summer, the Sun appears to rise in the Northeast and set in the Northwest, accounting for a relatively long day length
  15. Recognize the Sun is never directly overhead when observed from North America
  16. Relate the axial tilt and orbital position of the Earth as it revolves around the Sun to the intensity of sunlight falling on different parts of the Earth during different seasons
Whew! And that isn't all! So amazing to cram so many important objectives into one activity.
Source for most of these objectives:

NOTE: Here are the links to the rest of this series:
Measuring the Sun's Movement
Building the Sun Clinometer
Teaching Azimuth and Using a Compass Rose
How to Teach Altitude
Using the Clinometer
The Clinometer Activity