Lafayette Parish voters will decide April 29 whether to pay an extra half penny in sales tax for the next 10 years to fund a major school improvement plan that has picked up a growing list of endorsements in recent weeks.

The sales tax, which comes six years after voters shot down a proposed property tax with a similar goal, would be dedicated to roughly $195 million worth of projects in an effort to eliminate more than half of the 420 temporary classrooms in the district.

On Wednesday, a group of Lafayette leaders that included Sheriff Mark Garber, Assessor Conrad Comeaux, City-Parish President Joel Robideaux and Diocese of Lafayette Bishop Bishop J. Douglas Deshotel came together in a show of support at a press conference at Lafayette High School, which has 31 temporary classrooms that would be replaced with permanent ones should the tax pass.

"The old lesson of history is that any great and noble society is defined by how it cares for the children in that community," Deshotel said.

He said the proposed sales tax is "a small sacrifice that will reap a great good."

Robideaux said he believes a better school system is critical to the parish's future.

"That's the closest thing we have for a silver bullet," he said.

The school system has relied for decades on portable buildings to accommodate student populations that have far outgrown facilities. Some campuses have enrollments more than three times the original design capacity of the school.

"When you call something temporary and you still have it forty years later, it's probably time to stop calling it temporary,"  Superintendent Donald Aguillard said in an interview last week.

The list of tax-funded projects includes new schools for Prairie Elementary and Carencro Heights, expansions at nine other elementary campuses and a major addition to Lafayette High School.

In all, the newly built and expanded facilities would create enough permanent space eliminate 248 temporary classrooms.

The facilities improvement plan is not as ambitious as what Aguillard initially proposed to the School Board, but he said it will make a significant dent in a facilities backlog estimated at more than $1 billion.

"My gut reaction is that people understand the need, and I think they understand that the request is reasonable and thoughtful," Aguillard said.

The School Board voted unanimously to put the tax on the ballot, and the measure has gained backing from the regional development group One Acadiana, which is publicly pushing for its passage.

The proposed tax also received votes of support from the Broussard City Council, the Lafayette City-Parish Council, the Scott City Council, the Carencro City Council and the Lafayette Parish Association of Educators, among other groups.

"It's become evident over many years that our school buildings are in rough shape," said LPAE President Jonathan Cole, an educator at Lafayette High School.

Cole said it can be difficult to teach in portable buildings with rattling air conditions and rain beating down on the roof, and students are forced to dash through bad weather to get to classrooms disconnected from the main campus.

"It felt like you were removed from the community of the school," Cole said. "It makes for a very excluded situation."

Despite the public support of several community groups and local elected officials, the tax has attracted opposition.

The vote of support by the Lafayette City-Parish Council earlier this month was not unanimous — two members cast "no" votes and one abstained — and critics are making their views known on the Facebook page "Citizens Against the School Tax."

A Washington, D.C.-based group working under the name of Policies for Louisiana's Future has sent out mailers opposing the tax and produced an anti-tax video that's making the rounds on social media.

Joyce Linde, with the local conservative group Louisiana Citizens Action Network, said she has nothing against better school facilities but feels the School Board should search harder in its existing budget to fund improvements.

"We feel like we pay enough taxes on every level," she said.

Early voting continues through Saturday.

Follow Richard Burgess on Twitter, @rbb100.​