There should be some basic life skills class that teaches all the stuff you actually need to know, like you said taxes, finance, balancing a budget (though god help us if anyone on the BoE teaches that)

Also, and this would probably be beyond the purview of a single school, try to give kids a reason why they might want to pay attention. We were always told "you'll need this in life" for math, but never why. So try to teach the subjects in a way that can help them, where they know what jobs math can get them, or science, etc. I bet many kids would take math more seriously if they were told "see those stock brokers in huge houses and nice cars, they need some understanding of math"