NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta on July 9, 2011. More details on the Dawn spacecraft mission here.
It's always a good idea to keep your students "up" on what spacecraft NASA currently has floating around "up there!" Check out the NASA website for a wealth of information on several current missions.
Example: The Final Mission of the Space Shuttle.
Go here for a search engine for educator materials for teachers, all grades!