Science of the Sun!
Science Standards Addressed:
Science Standards Addressed:
- · Use observation and questioning skills,
- · Uses senses to observe surroundings
- · Observe how energy does things (solar energy changes UV beads & sun-sensitive paper)
- · Observes that the sun warms the land which in turn warms the air
- · Knows that the sun is a star
Plus we snuck in some speaking and listening standards like asking questions, expressing ideas, following multi-step directions, and participating in discussions.
See a video of a similar afterschool science lesson that we did in 2009 at http://www.youtube.com/user/CCafterschool?feature=mhum#p/c/78621E57C85DFAAB/10/8nBVtFrXrV8
10 minutes
As the children arrived we played Good Day Sunshine, by the Beatles; Here Comes the Sun, George Harrison, Sunshine on my Shoulders, by John Denver, Walking on Sunshine, by Katrina and the Waves; and You Are My Sunshine, by Ray Charles.
We had a snack that once again was a hint of the science to follow. We snacked on Sun Chips and Orange juice, and the oh-so-subtle solar system centerpiece was another clue. We asked them to predict what the topic might be. Most of them shouted “the SUN” right away. Next week we are going to have to make it MORE difficult to predict the topic!
Madison snuck in some English and SPANISH language arts when she read them a poem that she wrote about our topic of the day!
SUN
Hot, Bright
Burning, Heating, Energizing
Sol, Fire, Space, Light
Shining, Twinkling, Sparkling
Estrella, Bright
STAR
To sneak in some MORE literacy, she read Bear Shadow, by Frank Asch – a story about a bear who was outside all day trying to get rid of his shadow because it scared away the fish when we went fishing.
15 Minutes
We learned about primary and secondary colors, while making true masterpieces. We squeezed these colored gels into zip top bags, and then placed them where the sunshine could shine through the window and through the beautiful bags of color. There were lots of “oohs!” and “ahhs!” as the kids squished and squeezed the bags to mix their colors into beautiful stained glass images. Complete Experiment Description
We also snuck in some literacy by having them spell their names and special messages by drawing letters with their fingers on their bags.
5 Minutes
We experienced Rainbow Glasses and learned that white light is made of all the colors in the spectrum. These special glasses have lenses that separate light into the colors of Red, Orange, Yellow, Green, Blue Indigo, and Violet. When you look through them, funky rainbows appear. It’s a little bit like when water vapor in the air bends and separates sunlight creating a real rainbow.
15 minutes
Nature Print Paper – this paper is coated with light-sensitive chemicals. These chemicals react to sunlight (undergo a chemical change when exposed to sunlight). When you put things like leaves, flowers, or paper clips on the paper and then expose it to direct sunlight for a few minutes, the objects block the light and create a white “shadow” or “negative” while the paper around them stays blue. Then we rinsed them in water for a few seconds to permanently “fix” the images on the paper.
20 minutes
Cheap Wal-Mart Beads
Madison said, “I had an idea of doing an art project with you. I thought you could make bracelets. I went to the store to buy you some beads with money from my allowance. The colorful beads were too expensive. I could not afford them, so I could only get these white ones.” We made bracelets, and then we took the kids outside. As soon as we got out in the sun they noticed the beds stared to change colors. “Wow!” They were shocked to realize they had been tricked. We explained to them that the cheap white beads were actually ultraviolet (U.V.) light detection beads that change color when exposed to U.V. rays.
U.V. Detection Beads. These beads are very good at detecting and indicating changes in levels of UV radiation. Madison told the group that brown prescription bottles were colored that way to protect our medicine from damaging UV rays. When we put UV beads in the prescription bottle we could see NO color change. Looks like the little brown bottles do a good job!
After we discovered this, we decided to conduct some experiments.
15 minutes
We discussed some of the things people use to block UV rays, like sunglasses and sunscreen. We decided to compare how two different types of sunglasses blocked the UV rays. We predicted that the $5 sunglasses labeled as 100% UV protection would block the sun better than the free kids meal toy sunglasses. We found that the beads protected by BOTH sunglasses were colorless when we removed the glasses. We concluded that more research would be needed to conclude anything!
Sunscreen Experiment - When it comes to sunscreen, there are lots of SPFs (Sun Protection Factors). We thought, “What if we protected the UV beads with different SPF sunscreens.” Since these beads are very sensitive to changes in UV, we decided to conduct an experiment - using the beads to look for differences in how bright the color of the beads would be when exposed to direct sunlight. To find out which sunscreens work best, we collected four strengths of sunscreen (SPF 2, 30, 50 &; 70). First we coated some zip top bags with the difference strengths of sunscreen similar to the way we would apply it to skin. We labeled each bag with the SPF of the sunscreen we applied. Then we placed the bracelets we made into the zip top bags. We put NO sunscreen on one bag for a control. Then we exposed the bags to direct sunlight and observed and recorded the results. We observed a big difference between the SPF 2 and the SPF 70, but NOT a big difference between SPF 30 &; SPF 50. We also observed that ALL sunscreens let some UV radiation through.
10 minutes
Nature Prints Experiment: We applied sunscreen (the same sunscreen that we applied to the zip-top bags containing UV detection beads) directly to the sun sensitive paper. Again we found that the SPF 50 & 70 were much better at blocking UV rays than the SPF 2, and 30 and ALL sunscreens allowed some UV rays to get through.
Nature Prints Experiment: We applied sunscreen (the same sunscreen that we applied to the zip-top bags containing UV detection beads) directly to the sun sensitive paper. Again we found that the SPF 50 & 70 were much better at blocking UV rays than the SPF 2, and 30 and ALL sunscreens allowed some UV rays to get through.
