A blogger's lament
I agree that writing is important, the (average) American school is not teaching it well, and that it is partially due to topic-apathy.
I would like to add that, in my opinion, an additional reason for the badness of writing education is just not writing enough. This might be a result of students thinking writing is just not important, taking the least-writing pathway, and still complaining (I was such a high schooler). Not sure how you fix that.
I'd add one thing: write to teach others, especially in school. One of the best ways to learn something is to teach it. Moreover, one of the best ways to engrain an idea within yourself is to teach it to someone else in your own words. What better way than writing it down? Think about it for a second.
Imagine a broken group of students: one group learns a lesson, while another studies a different one. Both are brought together. Then, one group teaches the novice section the lesson they learned, possibly even writing it out for them. And the other group can do the same. Talk about a real world lesson about using knowledge, writing, and interaction.