Printhttp://en.wikipedia.org/wiki/General_relativity
http://en.wikipedia.org/wiki/Introduction_to_general_relativity
http://www.physics.fsu.edu/courses/spring98/ast3033/relativity/generalre...
http://csep10.phys.utk.edu/astr162/lect/cosmology/gravity.html
http://www-history.mcs.st-and.ac.uk/HistTopics/General_relativity.html
http://www.physics.uoguelph.ca/poisson/research/agr.pdf
http://preposterousuniverse.com/grnotes/grtinypdf.pdf
http://star-www.st-and.ac.uk/~hz4/gr/hendry_GRwaves.pdf
6th grade
8th grade
9th grade
