Administrators of schools denied federal tax-exempt status in the past on racial grounds--and to whom President Reagan would now grant it -- say they don't discriminate against blacks and can't understand why anyone would think so.

It's just that no blacks ever apply.

For example, Bob Redd, head of the Prince Edward Academy in Virginia, says, "We've had Jewish people, we've had some Korean people, and so on. From that point, I think you'd call us an integrated school. We have boys and girls, so we're integrated from that point, too."

Prince Edward Academy, opened in 1959 as a result of desegregation ordered in the original 1954 case of Brown vs. the Board of Education, was the prototype for all-white private schools all over the South.

"Our people have always felt the operation of our schools was a local matter," Redd said, adding that the people preferred to stick with the Virginia Constitution, which then required separate schooling for blacks and whites.

Redd says his school never has received an application from a black student and that it is unfair to brand the school as racist.

With annual tuition now ranging from $1,225 to $1,275 for the school's 950 students, Redd says a tax break would help, but he's not counting on the government to deliver on their promises.

"We've been mistreated for 20 years, badgered, beaten, every other damned thing. We don't get excited about anything any more. All we've tried to do is run a quality school system for those students whose parents want to send them," he said.

South Carolina's Bob Jones University is one of the schools that sued to force the Internal Revenue Service to reverse its policy of denying tax exemptions to schools that discriminate. Bob Jones III, president of the university, says, "This is not a race case. It has never been a race case. It's a case of freedom of religion."

Of the Reagan administration's decision, Jones said, "God answered our prayers and delivered his people from the hands of the IRS tyrants."

The administration announced a week ago that it was abandoning IRS policy since 1971 of refusing tax exemptions to schools that discriminate on the basis of race. The White "We've had Jewish people, we've had some Korean people, and so on," says one administrator. "I think you'd call us an integrated school. We have boys and girls, so we're integrated from that point, too." House decision makes it unnecessary for the Supreme Court to rule in the Bob Jones case, but civil rights groups are trying to persuade the court to act anyway.

On Tuesday, after heavy protests from the civil rights groups, Reagan said he would work with Congress to enact legislation to prohibit tax exemptions to institutions that discriminate.

On Thursday, Jones asked his students to flood Washington with at least a million letters to members of Congress and administration figures pleading for "sanity" in the legislation.

Bob Jones University does not refuse admission to blacks, but there are fewer than 10 blacks in a student body of 6,300. Under court pressure in 1975, the school changed some of its overtly racial policies, but there is still a ban on interracial dating or marriage.

Jones calls his school a "fundamentalist Bible-believing" institution with rules based on the Bible. "One of our rules says that whites must date whites, blacks must date blacks and yellows date yellows. No one has been singled out for discrimination," he said.

He adds that if the government should also take a look at the tax status of the orthodox Jewish synagogues that do not allow blacks, at the Black Muslims who "discriminate against whites," and at the Catholic church, which does not allow women to be priests. "There's discrimination all over our society on the basis of religious belief," he said.

All over the South, private all-white schools--religious and otherwise -- are insisting that race is not the issue and that blacks simply are not interested in attending those schools.

In South Carolina, the principal of a 600-student school with students in kindergarten through 12th grade says that no black has applied since the the school opened in 1970.

"We have no blacks, but we do not discriminate against minorities. If they were interested, we would be happy to talk to them," she said. "We play football teams with blacks on them. We're not narrow-minded as far as that goes."

Jack Miller of the Sparta Academy in Evergreen, Ala., says he would also be willing to admit blacks, although there are none presently enrolled. "We have no law against it, no rule, if they will meet our standards."

He said his school was started in 1969 "in response to integration of the schools rather than freedom of choice."

The Southern Regional Conference estimates that by 1970 there were about 600,000 white students enrolled in segregated academies but that the growth began to slow in 1971 after the IRS decided to deny tax exemptions to such schools.

After that ruling, schools became subject to certain taxes themselves and their donors could no longer take tax deductions on their contributions to the segregated schools. During the 1970s the schools raised tuition and enrollment grew only to about 750,000.

The schools concede that they have been hurt over the past decade by the IRS decision, and Miller estimated that a change in the tax laws could increase enrollment figures by "at least one-third."

Jones said the tax break would help, but he believes donations will continue to flow, even if the government eventually rules that they can be taxed.

"This is a Christian school. They don't support us because they get tax exemptions. They support us because they believe in us," he said.

While colleges nationwide have been struggling to keep up enrollment figures, Jones said his school has continued to grow. "There's only one explanation. The Lord is in control here. He's looking over this school."