"This is the piece that's been missing." This reaction is common among educators engaged in AIW Iowa, an initiative that engages teachers and administrators in professional learning communities that are improving student achievement, increasing student engagement, and building a schoolwide professional culture focused on improving instruction. The framework for authentic intellectual work is shorthand for distinguishing between the more complex accomplishments of skilled adults and the usual work students do in school. Using data gathered from its statewide assessment, Iowa's Department of Education examined the performance of students in grades 3 through 11 in schools in which all teachers engaged in authentic intellectual work as their primary professional development for at least one year before administering the test. In comparisons in nine grades and four subjects for each--36 comparisons--students in schools implementing authentic intellectual work scored significantly higher in 26 comparisons, with higher percentages of students proficient in 32 comparisons.