Math skills are critical to a variety of careers and important for life skills ranging from budgeting and smart shopping to understanding the news. The Pennsylvania Keystone Exam is one path for high school students to demonstrate readiness for postsecondary success. Proficiency among historically underperforming students can show whether districts and education policymakers have made progress in closing the achievement gap between traditionally underserved groups and other students.

In 2019, 74% of students in Lancaster County and 45% of students in the Lancaster City School District passed the Grade 11 algebra exam, representing no change in the County and up from 39% in the District in 2018. In contrast, 54% of historically underperforming students in Lancaster County and 40% of historically underperforming students in the Lancaster City School District passed the exam in 2019, up 1 percentage point in the County and 6 points in the District in 2018. Lancaster County's 2019 proficiency rates were higher than statewide rates of 65% for all students and 44% for historically underperforming students.

Lancaster County has the highest proficiency rate among all students followed by Chester (73%), Cumberland (72%), and York (71%) and the highest performance rate among historically underperforming students followed by York (50%) and Cumberland (47%). Lancaster County's share of historically underperforming students in eleventh grade (42%) is similar to Lebanon (41%), lower than Berks and Dauphin (both 48%), and higher than York (40%), Chester (33%) and Cumberland (31%).

As assessments vary among states, it is not possible to include comparable data for the nation or other areas in this indicator. Data are from the Pennsylvania Department of Education.