JOHNSTON — Resistance from the teachers’ union has forced the Johnston school system to abandon its leading role in a $12.5-million project to dramatically upgrade science and math education across Rhode Island, school officials said yesterday.

The town’s top educators withdrew from the effort after learning that the district’s science teachers would not participate in the program, which Governor Carcieri last September heralded as essential for the development of a work force in an increasingly challenging global economy.

State officials say Johnston’s withdrawal will not delay the overall five-year effort to upgrade science across the state because they are confident they’ll find a district willing to take Johnston’s place. There is money for six districts to participate; five others are on board.

Neither Kathleen P. Kandzierski, president of the teachers’ union, nor Robert Casey of the Rhode Island Federation of Teachers, responded to several requests to explain their union’s reasoning. However, Kathryn Crowley, assistant superintendent, linked the union’s refusal to its dissatisfaction with the way contract negotiations are going.

Teachers have been working without a contract since Aug. 31. The union and the School Department are currently involved in mediation.

Johnston’s teachers have stopped chaperoning dances and doing other tasks that aren’t required by contract, administrators say.

This time, they have gone too far, according to the schools’ lawyer, William J. Conley.

“There is a time when they need to put negotiation strategies aside and put the benefit to students and to the entire state first,” he said.

“Here’s Johnston looking to take a leadership role and have Rhode Island be in a leadership role, and the teachers are placing a work-to-rule strategy over all those values,” he said. “I think that’s an absolute tragedy. I hope they reconsider.”

The effort to upgrade science and math instruction is being supported by the National Science Foundation. The districts still participating are Cranston, Woonsocket, Lincoln, Scituate and Coventry. Other districts will follow in the coming years.

The grant, which is being administered by the University of Rhode Island, was announced with great fanfare last fall, during a news conference held at Johnston High School.

The program was described as an unprecedented effort to beef-up high school and middle school science education with tools, guidance and knowledge from university campuses, including those of Brown University, Rhode Island College and URI.

To get started, participating teachers will be asked to provide information about what they think is lacking in their districts’ curriculums and also to suggest what they think is missing in their own science knowledge. Then, this summer, the teachers from the six participating districts will take several short-term courses on science subjects tailored to fill the needed content.

They also will learn how to teach students to carry out their own scientific inquiries. And, they will learn to use new computer software as well as other devices to expand their teaching repertoire.

When the grant was awarded, Johnston was celebrated as the first district to volunteer to participate.

Carcieri announced the news just a few days after he had unveiled depressingly low scores from the state’s first standardized science test, which had evaluated the students’ skills of scientific inquiry and their knowledge in the earth, life and physical sciences.

In Johnston, only 16 percent of its 11th-graders were proficient in science.

“We could have gotten things that we normally could not afford, especially in this economy that we’re in,” Schools Supt. Margaret Iacovelli said yesterday when asked about the district’s withdrawal from the program. “I’m really disappointed.”

mreynold@projo.com