This is a question that I hear all the time. And you know what? Very few high school students really know what they want to do when they grow up.
When I was growing up computers were something we had heard about but had never seen. My first experience with a computer was in high school. We had a teletype machine (look it up) and created strips of paper with holes punches in them using BASIC language. We would send that strip of paper over a phone line to a computer 200 miles away and it would create our program and send it back to us several days later.