This digital world calls for changed mindsets about schooling, teaching, learning, and assessment--and engaged teaching matters more than ever. Combining inquiry and technology opens the door to powerful new teaching and assessment practices that result in documented benefits for learners. To realize these benefits, teachers need support in making major shifts in their practice: how they work with disciplinary knowledge, how they design for learning and assessment, and how they embrace technology. It is time for top-down approaches to schooling to give way to the active, engaged, and collaborative teaching and learning relationships made possible by new educational technologies. But how do we provide rich and meaningful professional learning opportunities that engage teachers in making the shifts that are required of them in blended and open participatory digital classrooms? How do we help them prepare young people to make the most of the technologies at their fingertips? (Contains 16 endnotes.)