Students want to belong. Transforming the way high school is done and allowing teachers to form more of a team approach (sort of like academies, but smaller, and more focused) would allow students a chance to be a part of a group--something special. We've seen this effect in SPIRE, where students are very excited to be a part of something special and different. We could do so much more with other teachers and a clear focus of integration and of relevancy for the students.
Each team of teachers can use the team set-up to develop integrated approaches that best work for their students. Critical thinking skills can be developed as teams work for the semester/year to answer an overarching question of their choosing. This will also allow teams to form context for their lessons.
This approach would allow for extreme flexibility within a school day. No longer will students be forced to sit through 4 classes in a row, which is tiring and repetitive. A longer block of time allows for teachers and students to set up a variety of experiences.