The journey toward 100% proficiency is most successful when a whole school works as a team. School leaders must focus their school's energy and effort on schoolwide initiatives that will make the changes needed to increase student learning and improve students' scores on state tests. The structure of the school and the collaboration of the faculty are vital to support the change. Schoolwide initiatives in reading and math, creative use of the schedule, and changes to the curriculum help all students learn--and improve test scores. This article features Penn Manor High School in Lancaster County, Pennsylvania, and describes its adoption of a schoolwide, collaborative approach designed to improve students' math and reading scores. During the 2006-07 school year, Penn Manor was recognized by Standard & Poor's for closing the achievement gap of its socioeconomically disadvantaged subgroup. Penn Manor was also recognized locally for making the greatest improvement in overall proficiency (20% increase) of the 17 school districts in Lancaster County during the past five years. Penn Manor's success was the result of both long-term programs and short-term goals. Initiatives included: (1) A schoolwide reading initiative; (2) A focus on a common curriculum and common assessments; (3) Collaboration on staff development, within and across departments; (4) Increased use of data to analyze effectiveness of curriculum and instruction and to identify students in need of additional support; and (5) Schoolwide support of special education students.