Once students reach high school, it is particularly important that they earn the best possible grades as well as high standardized test scores (SAT and/or ACT). NASA looks for the best and the brightest, so it makes sense that they would look at how well students apply themselves to their studies. At this point, too, students should begin to think about a specific direction of study, such as engineering, biological or physical science, or mathematics. This will help them direct their education once they get to college.
Again, though, books are only part of the process. It's a good idea to look for out-of-school opportunities like internships or apprenticeships, summer programs, and fieldwork, to help balance textbook learning. After all, going into space is a real-world -- not a virtual -- experience; the more experience you bring to it, the better you'll be able to deal with the demands of the job. Internships are also a good way of finding out if your career choice is the right one for you. Many students, when faced with the realities of a particular field, decide it's not what they wanted, after all. It's better to decide early on that this is the case, before you devote a lot of time and effort to something you don't enjoy.
But choose your activities wisely. "If you do things thinking that, 'This will look good on a resume, or 'I'm not going to like it but it'll help me get selected someday,' you will do yourself a disservice.
