Forced to choose the assessment method that is most likely to gain the needed approval - or else face the possibility of entering the next fiscal year without a budget - the regional high school district committee voted Monday to continue using the long-held enrollment-based formula in the regional agreement, rather than the "statutory" formula put forward by the state.

The matter now will go before voters at the annual town meetings this spring in the six Vineyard towns.

The final outcome carries financial consequences in the towns that could run into hundreds of thousands of dollars.

Under the recommended assessment formula - which will require approval from all six Island towns to override the state formula - the portion that each town will pay toward the regional high school will be similar to what it has been in the past.

If even one town votes against that formula, however, the regional district will likely end up using the state's method.

Of the Island's six towns, Oak Bluffs likely would benefit most from a switch to the state's method, while Tisbury would fare the worst.

According to data released last week by the state, the town's assessment would fall more than $413,000 next fiscal year under the state's statutory formula - an even more positive outcome than the Department of Education projected last November.

Meanwhile, Tisbury's assessment would increase by more than $220,000.

These most recent projections are still subject to change, however, until the legislature approves the state budget.

At Monday's school committee meeting, seven members voted for and two against staying with the existing method, which superintendent of schools Dr. James H. Weiss recommended to them.

"I have been agonizing over what kind of recommendation to give you," Mr. Weiss told the committee, but he ultimately decided on the regional agreement's method - "the one that has worked for better or worse for the last 57-some odd years."

Although the committee certified the regional high school budget in December, it waited to vote on the assessments until this week. As a part of new regulations approved by the state Board of Education in January, the school committee of a regional district must choose which method to use to calculate member town assessments and present to voters - rather than town officials choosing.

One Island town - Oak Bluffs - is strongly opposed to using the existing enrollment formula. The town leaders say Oak Bluffs should have lower assessments because it hosts the high school - and the statutory formula would offer them that reduction.

But selectmen in Tisbury, Chilmark, Edgartown and West Tisbury urge analyzing and updating the long-held assessment formula in the regional agreement instead.

The state's statutory formula is said to be based on "wealth," but actually depends on myriad data, including what appear to be 1994 student enrollment numbers.

According to the Department of Education, all of the Island towns are too "wealthy" for income to have an effect on the assessments. Despite contentious debate for the last six months about the two assessment methods, town and school officials do agree it is unlikely they will ever fully understand the state's method of calculating regional school assessments.

This is the first year the Island's regional schools have been faced with a choice of assessment formulas, since they were unaware of the state formula before - even though it dates back to 1994.

The state assessments are usually final by June or July - long after the annual town meetings - and sometimes drag on until November, according to assistant superintendent for business affairs Amelia (Amy) Tierney. The state's fiscal year does not begin until October 1, whereas the towns' and schools' begins July 1.

The gap in time would create some uncertainty in town budgets every year if the regional schools use the state's assessment method.

"We advise you to construct your local budgets with sufficient flexibility to accommodate the changes that typically occur in the state budget process," the state Department of Education's Web site states. "The commissioner will issue the final, official school spending requirements as soon as the Governor and Legislature approve either the FY08 state budget or an earlier local aid resolution."

According to the new calculations, the statutory formula also would reduce Aquinnah's assessment by $60,000 - notably less than the department formerly projected. The four other Island towns would be assessed at $70,000 to $220,000 more under the statutory formula, which would make up for the reduced assessments in Oak Bluffs and Aquinnah.

The statutory formula, had the school committee chosen to use it, would have required two-thirds of the member towns' approval - four towns in the case of the Vineyard regional high school district - to pass the budget.

The Up-Island Regional District Committee will vote Monday on which formula it will choose to calculate the district's assessments. The committee will meet at 5 p.m. at the Chilmark School.

Unlike the other towns, the Aquinnah board of selectmen did not send a letter to the high school committee endorsing an assessment method.

However, at its special town meeting last night, voters considered a non-binding article submitted by the selectmen to "require" the town to use the state's statutory formula. The article was recommended by the finance committee.

Although Dr. Weiss originally thought the enrollment formula could not realistically gain unanimous approval of the towns, attending the two all-Island selectmen's meetings last month led him to believe the Island could collaborate and fine-tune the regional agreement to satisfy all towns.

"I was taken, I must say, by the conversation at those two meetings," Mr. Weiss said.

He concluded that recommending the regional agreement's assessment method is an opportunity for the towns to retake control of the budgetary process, rather than give the state that control.

"I don't want to take that opportunity away from them," he said - although the decision is not without risk. "Whether they take that opportunity - that's your best guess."

He said he expects town leaders to continue talks before the town meetings.

If the regional high school budget - which is presented to each town in the form of its assessment - is not unanimously approved by the towns, the regional school committee would take the budget back for revision and submit it again at special town meetings called in each town.

If the school committee cannot pass its budget by July 1, the state would get involved. The education commissioner would establish an interim budget and if a budget was still not approved by Dec. 1, the commissioner would assume control of the district and establish a budget.

"While there's nothing written in the rules about what method he would use, he has basically indicated to me he would use the statutory formula," Mr. Weiss said, noting that it is unlikely the commissioner would make any changes to the budget itself.

In the meantime, Mr. Weiss has invited consultant Mark Abrahams from the Abrahams Group to hold a workshop next Wednesday from 2 to 5 p.m. in the regional high school's library conference room to clarify the state's statutory assessment method.

"There has been a lot of misinformation out there," Mr. Weiss said. "This is an opportunity for all of us at least to be on the same page."

Several school committee members questioned whether town leaders could come to any kind of compromise or adjustment in the existing regional agreement before town meeting, which would give voters in Oak Bluffs and Aquinnah confidence that they would not simply be giving up a windfall of money by continuing to use the long-held enrollment formula.

Committee member Jeffrey (Skipper) Manter of West Tisbury called it "not realistic" that every town would approve its assessment of the regional high school budget at town meeting this spring.

David Morris, an Oak Bluffs school committee member, said he is in favor of keeping the regional agreement's assessment method.

"As an Oak Bluffs resident, I know I'm going to fight on town meeting floor," he said. "I'm going to hope and pray Oak Bluffs taxpayers - as residents of the Island - will see beyond the boundaries of Oak Bluffs."

Mr. Weiss pointed out that if the district uses the state's statutory formula, it would be subject to adjustments and changes every year. He also noted that the Vineyard, because of its property values, or "wealth," compared to the rest of the state, will never fit the mold of the state's one-size-fits-all assessment formula.

School committee member Leslie Baynes of Edgartown said "I would like to think that meetings are going to move aggressively" to make progress on the issue before April 10, when four towns hold their annual town meetings.

"Oak Bluffs has been put in a terrible position," he added.