Grace Llewellyn speaks directly to teens, encouraging them to consider the unschooling option. Philosophically, Llewellyn differs from most Christian homeschoolers. Because of this foundational divergence, you might disagree with some of her logic. However, she has exceptional insight into much of the flawed logic of compulsory schooling and its incarnation in traditional high schools.
Rather than bore us with a recitation of philosophy, Llewellyn writes in a friendly, big sister style, using lots of stories and examples. She does not reject the idea of learning, but suggests better ways to learn than attending school. She even has sections with suggestions for covering basic subject areas for students who either are college bound or want to study those subjects for personal reasons. She gets into work, apprenticeship, entrepreneurships, and all sorts of other real-life options.
Although the book is written to teens (there is an introductory chapter written to parents), because Llewellyn's philosophy is a major part of the book, I would encourage parents to also read the entire book and discuss differences of opinion with their teens. In spite of philosophical conflicts, I recommend this book to challenge and expand your thinking about how to "do" high school.