I agree with Critter. School teaches you how to learn and be a critical thinker. It also teaches you a lot of other life skills like time management, multi-tasking, being a team member, etc. It also teaches you to take knowledge from one or more disciplines you may know and apply it to something else you don't know. It also teaches you to do your own thinking and be a healthy skeptic. Don't just take everyone else's word on everything, do your own research, find your own answers and come up with your own conclusions to things. Also, in a general sense, the more education you have, the more informed decisions you can make.
I think some of the most beneficial classes I have taken were for my business degree. All throughout my life it has helped with correspondence, accounting, taxes, etc. Also, I think everyone in high school or college should be able to take a basic business law course. That class has helped me a lot over the years dealing with life finances and business dealings.
And yes, typing in high school did turn out do be an excellent choice for an elective!