I've had time to think about this further since my last post. The Sun certainly peaks in the blue-green area of the spectrum. With the peak around 480nm "Solar Irradiance Data" <http://hyperphysics.phy-astr.gsu.edu/hbase/vision/solirrad.html>
At the surface it can be seen that the irradiance is approximately equal for each color. The idea that it's green is most likely based on the theoretical blackbody curve for a star of a certain temperature (I'm not sure about this.) Although it may only be coincidental Red + Green light gives you yellow, although you've said that there isn't enough blue light scattered from the path, i don't know about this, i'll certainly ask my Optics Professor. It must be remembered the "yellow" of the sun really isn't that "yellow." i've projected the disk onto paper and its not /that/ apparent. It would seem most likely at this time that it is a physiological effect. As for the children painting the sun yellow? What is this supposed to mean? Kids look at the sun, or they're born with the idea of a yellow sun?!