The head of America's largest teacher union is proposing that each state make at least one school district a "learning laboratory" where educators and others could freely experiment with school reform.

Such districts would have broad freedom to "redefine not only what we teach, but how we teach America's children," National Education Association President Mary Hatwood Futrell said in a speech scheduled for delivery at today's opening of the 1.9 million-member group's annual convention.More than 8,000 NEA delegates meeting at the Superdome were to vote later today on the proposal, which Futrell called "our most ambitious reform effort to date."

Reforms in laboratory districts could include more flexible school scheduling, partnerships with colleges, financing through means other than property taxes, and curricula managed by classroom teachers, according to a paper being distributed to delegates.

However, Futrell stressed that reforms could take many shapes.

She also said change should not be dictated from outside the laboratory district, but should be determined by local teachers, school administrators, parents, businesses and others.

Delegates of the rival, 677,000-member American Federation of Teachers, holding its annual meeting in San Francisco, endorsed another reform experimentation proposal Sunday.

The AFT version would pave the way for experiments in 1,000 or more districts, where groups of six or more teachers would be free to operate schools within schools.

The 3,000 AFT delegates also approved a resolution calling for curbs on standardized testing of kindergarten children, an idea that has caught on in Minneapolis and Georgia in recent years.

Both unions seemed to agree that school reform dictated by state governments had either failed outright or had gone as far as it could.