Any high school student interested in becoming an astronaut will be interested in any number of study areas including maths, physics, science, electrotechnology and biology. Many astronauts are also pilots who will be trained rigorously by either government bodies such as NASA or private companies such as SpaceX.
Some famous astronauts include: Neil Armstrong, Buzz Aldrin, Pete Conrad, Yuri Gagarin, Valentina Tereshkova and Dr. Sally Ride. You can find out more about being an astronaut here at wikipedia.
Space law and regulation
Space program manager
Space archaeologists and space anthropologists
As an astronaut, your subjects of interest to explore includes a number of intersecting areas:
Bachelor's degree in engineering, biological science, physical science, computer science or mathematics
Responsible, Resilient, Flexible, Quick Thinking, Honest, Reliable, High Risk Threshold, Peak Health & Fitness, Tech Savvy, Maturity.