Happy New Year! Did you know that 2015 is the International Year of Light (IYL)? IYL is a “global initiative adopted by the United Nations to raise awareness of how optical technologies promote sustainable development and provide solutions to worldwide challenges in energy, education, agriculture, communications and health1”. IYL is sponsored by several organizations with interests in science and science education, including the European Physical Society, the Institute of Physics, the American Physical Society, and the American Institute of Physics. You can find several lesson plans, videos and other educational resources on the IYL website2.
Last year I wrote about a very simple experiment can be done using water, a plate and M&M’s candies. The experiment can be seen in the video below:
In this Activity, students dye fabric squares with two plant dyes: aqueous extracts of tea leaves and of marigold flowers. They investigate how the addition of iron to a dye bath affects the resulting color and fastness of the dyed fabrics and observe that the type of fabric affects the results. This Activity can accompany a discussion of the impressive array of chemicals produced by plants.