The percentage of Virginia students passing state math exams plunged this spring, as the commonwealth rolled out more difficult tests in an effort to ensure students are prepared for college.

State officials said they were prepared for the drops, which ranged from 13 to 27 percentage points, since scores also dived when the Standards of Learning, or SOL, tests were adjusted in 2006. Virginia is gearing up to increase the rigor of its reading, writing and science standards next spring.