More than 1,000 Jewish college and high school students from New York demonstrated here yesterday against the Carter administration's plan to sell warplanes to Saudi Arabia and Egypt as well as to Israel.

Since the crucial vote approving the sale already had been taken by the Senate on Monday, the demonstration had a slightly academic quality to it. But, organizers of the march explained, they decided to go ahead with it to protest the administration's Middle East policy and to let the White House know that the Jewish community "will never be silenced."

Almost from the moment they stepped off the train and began the march from the Union Station to the Capitol, the domonstration leaders were conscious that behind every tree might be lurking a television camera or a still photographer.

"Can we get all the symbolism in the front, please?" asked Rabbi Avraham Weiss, 33, of the Hebrew Institute of Riverdale, as the demostrators came pouring out of Union Station. Weiss also expained each symbol. The people wearing Jimmy Carter masks with kaffiyeh - the traditional Arab head-dress - symbolized that Carter had "sold out to the Arabs," Weiss said. Persons wearing Carter masks on both sides of their heads symbolized that he was "two-faced - that what he said during the campaign isn't what he's saying now."

The group also carried coffins - small, medium and large - representing Israelis killed during 30 years of conflict with Arabs, and perhaps, as some put it, "the death of American morality."

The U.S. Park police carefully shepherded the group - four abreast in a line extending several blocks - from the station to the Capitol. A moment of confusion occurred at the outset when several Israeli flags were bunched at the front of the procession while American flags were sprinkled behind. This situation was corrected by Rabbi Rubin R. Dobin, chairman of the Israel International Information Council, who hurried about, shouting, "American flags up front, please. Let's get American flags up here, to the front. To the right. To the right. American flags to the right."

The demonstrators came from a variety of schools in New York, including Yeshiva University, Stern College, Vassar, Barnard, Columbia, Brooklyn College, Queens College, Yeshiva University High School, Manhattan Hebrew High School and Yeshiva Flatbush.

At the Capitol, the demonstration heard a series of speeches by Sens. Lowell P. Weicker Jr. (R-Conn.) and Daniel P. Moynihan (D.N.Y.), and Reps. Robert F. Drinan (D-Mass.) and S. William rabbis who accompanied the group.

"The vote on Monday," Rabbi Shlomo Riskin said, "will in the annals of history in blood. Mr. President," Riskin said, directing his remarks at Carter, "you have forsaken us."

Rabbi Shlomo Berman, of Yeshiva University, said that if Carter really believed that the plane sale to Saudi Arabia would make Israel more secure, "we would like to invite your daughter, Amy, to attend school on one of our northern (Israeli) border settlements."

After the speeches, the demonstrators trod the familiar path from the West Front of the Capitol up Pennsylvania Avenue to the White House.

There, seven rabbies, including Dobin and Weiss, handcuffed themselves to the White House fence for 75 minutes to protest Carter's Mideast policy, and a memorial service was held in Hebrew. Park police did not arrest the rabbis, Maj. D.R. Sorah said, because they had broken no law.