With the backing of Virginia Gov. Charles S. Robb, state Board of Education members indicated today they are likely to approve an overhaul in the state's public school curriculum this summer and significantly toughen requirements for a high school diploma.

Board members, who met with Robb over lunch at the Executive Mansion, emerged later to say there is too much "fluff" in the public schools and that academic standards are too lax.

"We are doing a disservice to our children by not expecting more," said Margaret S. Marston, a board member from Arlington. "I think it's very likely there will be significant changes made."

Robb used the lunch today to renew his repeated calls for more rigorous standards in the public schools. In a press conference outside the mansion afterward, the governor sharply disputed charges made by critics, including many Northern Virginia school officials, who say his proposals are "elitist" and would result in a return to the tracking of public school students.

"Absolutely not," said Robb when asked whether his proposals would foster elitism. "We're talking about an aristocracy of merit. There is nothing elitist about that at all.

"We've permitted the standards to be relaxed to accommodate the marketplace."

Robb's comments come amid a mounting statewide debate over educational standards, a debate triggered by sagging test scores and concern that students are ill-prepared for the nation's emerging high-technology economy.

A series of proposals by Superintendent of Public Instruction S. John Davis, due to be considered by the board this summer, calls for longer hours of study and more stringent requirements in mathematics and sciences. Students would have to take at least two years of math and two years of science, as well as a fifth course in either math or science to receive a diploma. Currently, they only have to take one year of math and one year of science.

Davis would also create a special "advanced studies" or college preparatory program that would require a B average or better, allow for fewer electives and lead to a special seal on the high school diploma.

Robb, however, said that if anything, the Davis proposals were "too timid." He preferred instead that the board approve the full slate of recommendations recently made by the National Commission on Excellence in Education, which includes even tougher math and science requirements.

The special "college prep" program is likely to be the most hotly contested item before the board. Critics, including the Fairfax County School Board, have charged that this would ostracize public school students who are not qualified to enter the program and downgrade the importance of alternative programs of study, including vocational education. They also say it would allow less time for music, drama, fine arts and other areas of the liberal arts.

Marston, who served on the national commission, disputed this, saying there are far too many electives being offered right now in the schools.

"They school systems should look at cutting out the fluff," she said. "By fluff, I mean, 'Adulthood and Preparation for Marriage and Sign Painting.' "

Alongside the debate over standards, there is a separate dispute over the state Department of Education's recently proposed $3.1 billion budget for the 1984-1986 fiscal cycle--a $812 million increase that even department officials acknowledge they are not likely to receive.

Despite his high priority placed on improving education, Robb said today he would not hesitate to give the same kind of budget scrutiny to the department's request that he is giving to other areas of state government. But, he said he was not ruling out a possible statewide tax increase to fund education, although this was not on the "immediate agenda."