As a college freshman, here's my view on high school work: just do it. It's the only way to get into college. That has to be your sole motivation, as for most intelligent people, high school work in itself is not interesting in the slightest (although I was lucky to take a Constitutional Law class senior year that I loved).
However, don't despair: college work IS interesting. Unlike high school, a college will let you take essentially whatever class you want. Interested in physics? Take a class on special relativity. Interested in philosophy? Take a class that applies the theories of the great philosophers to modern moral problems. Interested in spaceflight? Take intro to aerospace engineering. At a university, the possibilities are endless, especially freshman year when you don't have to worry in the slightest about your major.
So, to sum it up, this is my advice: high school work sucks, but college, at least from what I've found, is awesome. Not only are you encouraged to take classes in areas that interest you, the atmosphere and social life is also incomparably better than high school. Your motivation thus should be directly tied to college: if you do not do this paper tonight, you will not get a good grade in this class, and you will not be able to get into as good of a college, meaning you may not be able to take high-quality classes in the areas that really interest you. It may seem like negative motivation, but if you view college as something good for you (and not just good for your career), it really becomes positive motivation. Good luck.
I agree with what you say about high school and heading to college. However, I am about a year or so away from finishing my undergrad in CS, and I have to disagree with the idea that college work is entirely interesting. It is true that most of the classes that directly involve your major are found to be more interesting to the individual. The problem is that colleges will require you to take classes that are not always directly related to your major.
For example, I am currently taking an upper division political science class, but only because it was required.
I have no real interest in this course, but my motivation to do the work is to never have to look at it again. I figure if I can do it, and I can do well, then I will never have to sit in this type of class again.
The other issue with college is professors. I have had interesting subjects with the most uninteresting professors. This definitely makes the subject matter more difficult to find interesting. The opposite, however, is great. If I have a subject that I can't stand, but a professor that is very excited and interested in the subject, it will usually get me really motivated to do the work.
Obviously, these are my opinions, so this will vary from person to person. My motivation for doing uninteresting work in college is to have one less obstacle between me and my future goals. I'm sure this motivation can be applied to many other situations.
Perhaps my opinion is colored by being a person interested in studying many fields. It is very true that if your interests lie entirely in your major, you will be forced to take classes outside of that.
However, don't despair: college work IS interesting. Unlike high school, a college will let you take essentially whatever class you want. Interested in physics? Take a class on special relativity. Interested in philosophy? Take a class that applies the theories of the great philosophers to modern moral problems. Interested in spaceflight? Take intro to aerospace engineering. At a university, the possibilities are endless, especially freshman year when you don't have to worry in the slightest about your major.
So, to sum it up, this is my advice: high school work sucks, but college, at least from what I've found, is awesome. Not only are you encouraged to take classes in areas that interest you, the atmosphere and social life is also incomparably better than high school. Your motivation thus should be directly tied to college: if you do not do this paper tonight, you will not get a good grade in this class, and you will not be able to get into as good of a college, meaning you may not be able to take high-quality classes in the areas that really interest you. It may seem like negative motivation, but if you view college as something good for you (and not just good for your career), it really becomes positive motivation. Good luck.