I is stuck.

OK
I was originally going to test the scattering of light (the process which shows why the sky is blue) and build me own model of the whole thing (light source, material/s it shines through to represent atmosphere, mirrors, results, etc.) but I got told today it has to be an ongoing experimented thing.

dang.

so now i've a various ideas on various things.
one - build, or get the same masses (volume) of objects of different materials, man-made and somewhat natural eg. steel, wood,platic, cloth, etc. and leave them under climatic conditions (in other words, outside), observing their rates and appearances of change.

two - collect rocks from different parks/beaches, observe THEIR reactions towards rain, sun, winds, local air. then determine their composition through research.
three - test stability, by building models (preferably out of cardboard and glue :)), assesing area to area ratio, and their impact on the object as a whole.
i don't even know what i'm going on about anymore.

off to surf the world wide web for ideas!