Chances of becoming an astronaut?

I'm 13 years old (still in eight grade), and I want to know what the chances are for becoming an astronaut. Usually whenever I hear about it, I always get the same answer: 1 out of (pick a number between 1,000-100,000). Will the chances be greater by the time I graduate from highschool? I thought that maybe since NASA is getting more and more advanced in technology etc., they would be sending more and more people into space, which would increase the chances of becoming an astronaut. Another thing I want to ask is how will I become an astronaut? What degrees should I get etc.? Is becoming an astronaut a practical career to pursue? Thanks.