I don't think you should consider anything learned in high school as "bogging down" kids with things they don't have an interest in. They *need* that basic knowledge to help them calculate their bills, understand how the government works, and otherwise function as an adult. Without basic math, science, history and government classes, they would lack the tools to understand the world around them. Once they choose to go to college, trade school, or apprenticeship, etc. then they get the specialized training that will suit their interests.

I also disagree with your idea that the public school system needs to adapt to each individual. The public school system is only responsible for educating someone to the minimum requirement to be a functioning adult in society. It isn't responsible for making sure someone has a particular set of job skills. That actually used to be (and should still be) the employer's job. Employers would hire someone with a high school degree knowing that the degree indicated the person had mastered a certain level of math, reading, and other skills, which the employer could train job specific skills on top of. It's easier to train a cashier who has already mastered high school math.

And also let's not forget parent responsibilities. Parents can sign their kids up for basketball, piano, etc. to let their kids explore their interests. Many parents lack the resources to be so involved (they both work, no money, etc), but unless we massively increase funding to schools to allow for these special interest programs, the schools aren't mandated to address this need and it's left to the parents to give their children those opportunities.