Well why not shoot for getting a degree in mechanical (or electrical engineering) then go ahead and get some good experience close to what you WOULD want to do at Nasa. Then, after a couple of years call their HR office and then submit your resume.
Most importantly, study study study
howd o i get a job at nasa? even cleaning the floors or something loll i dont care theyd pay good :P...like what courses and stuff would i take in college or university to even work in the building any where as the lowest scum job in there?