to develop and test technologies for exploration spacecraft systems, develop techniques to maintain crew health and performance on missions beyond low Earth orbit, and gain operational experience that can be applied to exploration missions http://en.wikipedia.org/wiki/Iss
Mars rovers were successfuly sent to mars and since then have had several more rovers sent. one is still in communication today. http://en.wikipedia.org/wiki/Mars_rovers
The Gemini Project was the second manned spacecraft missions and their goal was to collect the information they needed to get a man on the moon. http://en.wikipedia.org/wiki/Project_Gemini