Summer school enrollment in Prince William County appears to be outstripping the number enrolled last year, as students sign up for remediation classes based on their scores on the Standards of Learning tests.

Summer school administrator Renee Lindsay said some increase in enrollment was to be expected as a result of the tests, given to students in third, fifth and eighth grades and high school.

As of yesterday, about 4,200 students in elementary and middle school had signed up for summer school, a number "substantially higher" than last year, though direct comparisons cannot be made because records were maintained differently last year.

In high school grades, 658 students have enrolled in summer school classes. Last year, the number was 688. Because the deadline has been extended to register for high school summer courses -- from 9 a.m. to noon tomorrow at Hylton High School -- Lindsay said she expects last year's enrollment will be easily surpassed. The high school deadline was extended to allow students time to receive report cards.

But some discount the SOLs as the main reason for increased enrollment.

Associate Superintendent for Instruction Pamela K. Gauch suggested part of the increase in enrollment at the high school level could be from students who did not receive a passing score on the required 11th-grade research paper. Students must receive a passing score on the paper to complete their junior year, and those who score low can rework it during summer school.

The numbers Lindsay quoted include only students who have signed up for summer school remediation, not students who are attending shorter enrichment "camps" to study writing or math.

The increase in summer school enrollment in Prince William is matched by other Washington area school districts. Fairfax and Prince George's counties are forecasting enrollment increases of 20 percent, Alexandria expects a 15 percent rise, and Montgomery County officials say registration for summer school is running about 10 percent ahead of last year's total.

Prince William has planned its remediation courses differently this year. Students who finished grades kindergarten through second will get extra help in math and language arts. Students who finished third through eighth grades, however, will get a pre-test to help teachers decide what subject area needs the most work. Then, the child will receive instruction designed to fix the biggest area of deficiency.

"We want to home in on what the problem is," Lindsay said.

The pre-testing also will help the school system determine the success of its summer school programs, Gauch said. By testing a student before and after the class, "we'll be able to measure the growth we make," she said.