Great read from Sam Altman, well rounded and sensible advice, providing enough context to help someone make a good decision:
No matter what you choose, build stuff and be around smart people. “Stuff” can be a lot of different things—open source projects outside of class, a startup, a new sales process at a company you work at—but, obviously, sitting around talking with your friends about how you guys really should build a website together does not count.
Can't disagree with that or, indeed, anything else in this article. If you're an ambitious 15-19 year old, have a read.