When the U.S. space agency pinned badges on the 11 newest members of its astronaut corps this winter, it also increased by three its cadre of educator astronauts. Three former teachers-Dorothy M. Metcalf-Lindenburger, Richard R. Arnold II, and Joseph M. Acaba-graduated from NASA's grueling training program. The gauntlet of fitness test, survival and technical training, and dawn-to-dark studies began shortly after their selection out of thousands of other K-12 educators who had applied to the space program in 2004. The educator astronauts said they expect to work with teachers, in part, through a network of 194 teachers formed from those who applied to be astronauts in 2004. Members of the Network of Educator Astronaut Teachers, a volunteer group, receive professional development from the space agency, and, in turn, train other teachers. The network holds an annual conference at a NASA facility.