Each year for the past 3 years, the Virginia Department of Education has updated their standardized tests known as the Standards of Learning (SOLs).
The SOLs are administered toward the end of the year to all students starting in grade 3. These tests are one way to try to objectively measure the performance of a school.
The intention of the SOLs is to measure how well the school districts are educating the students, so each year, they challenge the kids a little more, and they make the tests a little bit harder.
For example, the overall SOL passing rate* for all of Virginia has gone down the last three years due to the tests getting tougher: