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Science project flopped

Postby mosobczak » Sun Nov 25, 2007 8:50 pm

My son has worked on his science fair project for 2 weeks. He used a house plant, made transparent sleeves of different colors to log the changes of the leaves and hung it in a sunny window. It was supposed to show us how wavelengths effect the leaf. When we removed the sleeves after 2 weeks, no changes were noted. What should we have noticed in the leaves?

Colors used, red, blue, green, yellow, clear & black construction paper.
Thanks for any help, you can offer.


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Postby barretttomlinson » Mon Nov 26, 2007 12:23 am

I assume you are attempting the the "leaves and Light" project in the Life Sciences/plant biology section of the Science Fair Project Ideas guide on this site.

For this topic you would likely get better answers by posting in the Life, Earth, and Social Sciences section, rather than Physical Sciences.

Having said that I would expect at least the leaf covered by black construction paper to turn a lighter green or white after two weeks. Other color sleeves might have the same effect if they effectively block the colors of light used by the leaf in photosynthesis. If the experiment did not produce the expected result, it might be because the sleeves were not colored completely, or the color was not intense enough to completely block the color of light.

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Postby tdaly » Mon Nov 26, 2007 6:49 pm

First things first: DO NOT STRESS. Science turns out in weird ways all of the time! Just because nothing happened does not make your time a waste and it does NOT mean that your son's project is a failure.

When doing a science project, it is important to base it on what you observed happen. I'm assuming that you already have a question, hypothesis, a list of materials, and a procedure. Now you have your observations. You noticed no change. That is perfectly valid. You just need to communicate that result. You likely proved the hypothesis false. This is OK. It is, in fact, excellent! Proving things false is a critical part of science. Just be sure that in your conclusion you "answer" your hypothesis based on your experiment. If it supports your hypothesis, fine. If it contradicts your hypothesis, that's fine, too!

Real scientists have experiments "go wrong" all of the time. In fact, botched experiments have often paved the way for major discoveries. Remember, you have done nothing wrong. You still have an A+ science project as long as you have followed the steps of the scientific method, made accurate observations, and reported honest results.

Let me know if you have any other questions or concerns.
All the best,

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Postby mosobczak » Mon Nov 26, 2007 7:43 pm

Thank you both for your response. I had my son read them and he has completed the project to turn in tomorrow.

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Postby Craig_Bridge » Tue Nov 27, 2007 7:35 am

What plant variety did you use? Some are extremely robust and are hard to kill like cactus.

Most plants share nutrients along a vine, stem, or branch system. Unless you treat the whole plant to the same conditions you might not observe differences.

All of your "filter" material also might have been sufficiently transparent to the wavelengths required when compared to the light source. In other words, the plant might have been getting enough light to meet its needs.

Plants have reserves. You might not have run the experiment long enough to exhaust the reserves.

Others have had similar difficulties with this experiment.

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