Exactly, it depends on intentions and since it depend on intentions, it would be unwise to force students to learn about everything in detail. The system should introduce all the information available and observe the students intentions. Once the intention is identified, the system should gear the courses based on that intention, thus not wasting time and resources. This should be done early.
Knowledge that has no practical value for the individual is useless and becomes a pleasurable activity. As with your example, you studied evolution because your intention was to know the world around you. This is a pleasurable activity, not a practical one. Is school a fun house or a place of practical purpose?
I actually have zero curiosity on the way things work. I buy a watch to tell time, not to analyze the mechanical operation. Materialism makes me happy, hence my intention is to make a lot of money to afford the best of it. The only way I saw/see that happening is in the financial industry since I have no salary cap.
I don’t need to learn politics, science, or arts to vote. I vote based on the above intention. For example, I can’t possibly vote for Barack Obama because he wants to raise taxes on me and regulate the industry that helps me achieve my goals. It’s the antithesis, hence I can only vote for Ron Paul who fits my intentions.
As for children, if I have any, I will hire professionals to teach them at home since I don’t have the skills nor the time to introduce each subject.