PORTLAND – School officials will watch student enrollment figures closely in the coming weeks, hoping that an unexpected increase won’t require them to hire more teachers.

Early figures show that an estimated 6,940 students have registered to attend Portland’s public schools in 2010-11, Superintendent Jim Morse told the School Committee on Wednesday night.

If that figure holds, it will be a slight decrease from the 6,992 students who were enrolled last Oct. 1, according to school budget documents.

However, Morse said the enrollment figures are expected to fluctuate through the start of classes, in part because some immigrant and economically disadvantaged students usually register late.

“The numbers in front of you are incredibly preliminary,” Morse said. “We’re within 100 youngsters of where we were last year, up or down. Whether classes are under-enrolled or over-enrolled, we really don’t know yet.”

Last year, Maine’s largest school district had an unexpected spike in enrollment that swelled classes in its elementary schools.

By mid-September, enrollment had increased to 7,008 students — 165 more than the 6,843 projected when school officials developed a $91.3 million budget for the school year.

The increase countered a 39-year decline in enrollment in Portland schools — from a peak of 14,188.

In response to the increase, Morse hired an additional teacher for a combined first- and second-grade class at Clifford Elementary School, and a teacher and three teacher aides to address large class sizes at Hall, Longfellow and Presumpscot elementary schools.

He covered the cost of the additional staffing by cutting other areas of the budget.

If this year’s enrollment calls for additional teachers, school officials will be working with an $89.9 million budget that eliminated dozens of positions.

Morse said he has asked Grace Valenzuela, multilingual program director, and Kevin Mallory, transportation director, to provide more solid enrollment figures for an upcoming School Committee meeting.

Kate Snyder, the committee’s finance chairwoman, asked that future enrollment data include a comparison with student counts that were used to build the current budget, “just to see how our predictions are holding against reality.”

Staff Writer Kelley Bouchard can be contacted at 791-6328 or at:

kbouchard@pressherald.com