Home School Science: Rainbows, Light, and Optics. Up to 7 hours Core credit.

I always appreciate the efforts made by people of good will to provide educational resources for children on the Internet. Especially, it seems in the area of Science, I often find enjoyable explanations appropriate for children. Today, while browsing Google Plus, I located a video I felt deserved to be passed along. This video runs approximately 10 minutes and explains rainbows and why they appear in arcs.

(The young lady's accent may be Ukrainian, I am not an expert in such matters.)

The young lady in this video has an accent which may be difficult for some people to understand. Of course, you can find other videos to watch.

With another 5 minutes of viewing, perhaps some of  the things said by the young lady in the first video can be reinforced somewhat. Some clarity, perhaps, could be achieved by the absence of a noted accent. However, the second video is a more simplistic explanation of the rainbows and does not cover the same details.

I would be rather remiss, however, to pass over a Bill Nye video.  Bill's speaks for 22 minutes on light and optics in general. During the course of this video, children should be able to understand how and why light bends when it slows down during transmission through glass or water.

During this video, several different experiments are performed in the interest of explaining optics. Perhaps your child could make a note of which ones they think could be performed at home with items you already possess. In particular, the bending of light during the penny trick and the internal reflection with the pencil in a beaker both seem easy and interesting. The later, however, internal reflection, may help make sense of why light would be reflected inside a falling spherical raindrop as explained in our first video. Later in the video, Bill uses a beam of light shining through green water to illustrate that internal reflection depends on the angle at which light hits the water to air boundary. This helps make clear how light can enter what seems to be a clear droplet of water and be reflected in order to create the rainbow.

Finally, although we wander rather far from our original investigation of rainbows, Season 1 Episode 5 of Cosmos: A Spacetime Odyssey contains another 42 minutes of "Core" science time tangentially related to light and optics. With the addition of this episode, our total running time comes to nearly 80 minutes. With 10 minutes to conduct a few of the experiments suggested in the Bill Nye video we should have an hour and a half of science credit.

However, if this is not yet enough coverage of rainbows and related optic phenomenon, your students may be able to to sit through a lecture on the topic by Walter Lewin who holds a PHD in astrophysics and taught at MIT. (He is now retired, a Professor Emeritus.)  His lecture runs nearly two full hours. Walter Lewin's MIT Page provides a few more possibly interesting videos with related content: The Mystery of Light (1 hr 22 min) and Polarization: Light Waves, Rainbows, and Cheap Sunglasses (1 hr 28 min.)

At this point, our resources related to rainbows, light, and optics round out to about 6.5 hours of core science credit for students willing to and able to listen to all the material. Students who take notes during this process should be able to write a half and hour summary of what they learned which was of the greatest interest to them. This is useful to show that the child was paying attention, but also in order to identify what resources most appealed to them.