An astronaut brought a down-to-earth lesson to students at three Sandy Springs schools Tuesday. Robert Satcher, here talking with pupils at Woodland Elementary, told them, "You have to take math and science classes if you want to be an astronaut." Satcher was part of a space mission in November. His school visit, launching a program called "Reach for the Stars," was a part of the STEM (Science, Technology, Engineering and Mathematics) initiative to prepare students to be part of the 21st-century work force. Satcher also talked at Dunwoody Springs Elementary and North Springs High School.