Students in two Suffolk schools were less likely than their counterparts around Virginia to graduate on time last school year.

King’s Fork and Lakeland high schools both had on-time graduation percentages below the state average of 86.6 percent during the 2010-2011 school year, according to the Virginia Department of Education.

Nansemond River High School’s rate was slightly above the state’s percentage.

Suffolk school officials were upbeat about the numbers.

“We’re encouraged, because we’ve continued to improve,” Suffolk Public Schools assistant superintendent Kevin Alston said. “With the exception of Lakeland’s drop this year, since 2008, there’s been steady improvement.”

As a division, Suffolk Public Schools improved slightly this year, with a graduation rate of 81.2 percent, compared to last year’s 80.5.

The division’s dropout rate also improved one percentage point, to 10.8 percent, but was still three points higher than Virginia’s 7.2 percent average.

The on-time graduation percentages are based on how many students complete high school in four years. Those students who were considered for the DOE’s study were in the class that entered as freshmen during the 2007-2008 school year.

This is also the first time that on-time graduation rates have been used in the state accreditation ratings. The sub-par numbers posted by King’s Fork and Lakeland caused them to receive only provisional accreditation this year.

Alston said the division is disappointed the two schools didn’t reach full accreditation, but he is still happy to see the improvements made in graduation and dropout rates since 2008, the first year the numbers were reported.

“We’ve come a long way in three years,” he said.

In that time, the division has improved its graduation rate almost 10 points, and the percentage of dropouts has plunged almost 12 points.

This year, King’s Fork had 78.6 percent of its 2011 class graduate on time, and while the percentage fell short of the state average, it is a five-point improvement from last year.

The dropout rate at King’s Fork also got better, decreasing three points to 13.4 percent.

While Nansemond River’s dropout rate improved slightly, its on-time graduation rate held steady.

In contrast, Lakeland’s on-time graduation rate fell, while its dropout rate rose from last year’s numbers.

In 2010, 81.5 percent graduated on time, while 78.3 percent did so this year. The dropout rate increased to 12.5 percent.

Although Alston isn’t happy to see the falling on-time graduation number, he thinks it might be “a one-year thing.”

“If it continues to drop, I would have problems,” he said.

Alston said one factor that could have lead to the decrease at Lakeland is the number of students who attended summer school.

“Of the three schools, (Lakeland) had the least students of any in summer school,” Alston said. “(Lakeland principal Thomas Whitley) didn’t have the number of students he normally has going to summer school.”

Alston said all of the principals are examining the results to see how they can have better numbers next year.

“They’re all looking at their data and trying to improve,” he said.

Alston said he hopes programs that the division has in place to improve graduation rates will continue to help.

He credits the improvements made in recent years to things like credit recovery classes, freshmen transition programs and remediation programs.

“Those are all things that are being done to try to improve our graduation rate and dropout rate,” he said.