"Strategic Inquiry" is an innovative model for promoting teacher collaboration around identifying specific "learning gaps" that keep struggling students from succeeding. Gaps may include anything from the proper use of commas and conjunctions to concepts such as "slope" in math. The authors argue that addressing these critical learning gaps can lead to big changes in student success, in teachers' sense of efficacy, and in school culture. The strategic inquiry model has been implemented in schools and districts around the country, including New York City, where it was rigorously evaluated with impressive results. As Common Core standards raise the bar for student learning ever higher, this proven approach promises to build teachers' capacity for closing the gap between where struggling students are and where they need to be. [Foreword written by Michael Fullan.]