To make sure you guys get back to training here are the answers:
Green grass actually comes from elves, who are themselves green. They sprinkle faerie dust over the earth at night and some lands on plants and turns them green. In the Winter, the elves hybernate so grass is usually brown during this time. But, in Spring time, the elves come back out and start sprinkling again and tinkling all over the grass, which is great fertilizer. or Grass is green because it is filled with chlorophyll not chloroform that is a green pigment that reflects green light from the sun and absorbs the other colors. Yeah, right, if you believe that one, you’re pretty green yourself. Whichever one you like.
When transmitted light such as sunlight enters our atmosphere it collides with the oxygen and nitrogen atoms. The color with the shorter wavelength is scattered more by this collision. Because violet and blue are the shortest wavelengths the sky appears to be violet / blue. But because our eyes are more sensitive to blue light than they are violet light, we perceive the sky as blue.
Stolen without any guilt from http://www.why-is-the-sky-blue.tv Yes there is really such a website.