What was going on when I was born?

CHAPPAQUA ''YOU may not see any major differences between the way classes are conducted here and at other schools,'' a teacher at the Horace Greeley High School was saying to a visitor the day after fall classes had begun. ''You will see students who are motivated. But you will also see students who are not prepared for the day's lesson. You will see teachers who are excited about their work and others who are not. ''Academic excellence just isn't something that necessarily comes out in the classrooms. At least not something you can physically see or touch.''

Those who find history boring might have dozed off as they watched it being made at the New York City polls last week. In a political coup that capped weeks of utterly bearable suspense, Mayor Koch became the first city candidate to win Decmocratic and Republican nominations.

THE pragmatist and the conservative true believer in Ronald Reagan fou ght over e conomic policy again last week. The true believer won. Calling for m ore slashes in domestic spending and just a nick out of defense, he d emanded that a weary Congress go back at the budget until they ge t it right. Even critics like Charles T. Manatt, chairman of the Democratic National Committee, conceded that the television address was ''as always, a good political speech.'' There was firmness, reassurance, and even an untypical call for sacrifice, along with the $13 billion solution.

RABBIT IS RICH By John Updike. 467 pp. New York: Alfred A. Knopf. $13.95. RABBIT ANGSTROM keeps coming back, like a song that says ''remember.'' Born deep in the well of John Updike's nostalgia, he summons Updike home. Not to Shillington, Pa., the hometown that Updike left behind some decades ago, but to nearby Reading and the suburb Updike calls Mt. Judge. Rabbit and Updike have a relation that may be unique in literature. Once Arnold Bennett created Clayhanger or Ford Madox Ford his Tietjens, each stayed with his character. Trollope wrote other books in between work on his Barchester and Palliser novels, but Trollope never focused his series on one place or character. Updike, though, published ''Rabbit Run'' in 1960, ''Rabbit Redux'' in 1971 -and now ''Rabbit Is Rich.'' In between, there has been no reason to believe that Updike cares any more about what happens to Harry ''Rabbit'' Angstrom than he does about characters he has been content to create and abandon. But then the summons comes.

MICHAEL JONES had been a Bell telephone salesman for 10 years when the company told him last spring that he would have to prove himself again. Mr. Jones, who requested his real name not be used, was told to write a report and submit other documents showing that he knew how to organize an account, knew the Bell product line, knew the Bell marketing strategies. He was given less than a month to prepare the report, on his own time. A special board of crack salesmen was set up to judge his dossier and those of his co-workers. ''I feel like it was kind of crazy to all of a sudden turn around and justify your existence,'' Mr. Jones said, who left Bell in June and now works for another telecommunications company. The American Telephone and Telegraph Company does not think it crazy. It is requiring all 6,500 of its account executives to be certified, a test so rigorous that one of the executives in charge estimated that only 15 to 20 percent are passing on the first try.

The Islamic Society of Westchester and Rockland bought the house at 220 Wortington Road last April for $210,000, intending to convert its three-car gorage into a sanctuary and to install quarters for a part-time religious school and caretaker's residence. Composed of about 40 families, the society had been holding Sunday services in a Unitarian church in White Plains and, before that, in rented quarters at the Westchester Community College in Valhalla. Religious uses in residential neighborhoods are allowed, with certain limitations, under zoning laws of the town of Greenburgh. One of those limitations was found to apply, however, to the Moslem Property, which stands less than 38 feet from its rear property line. Religious buildings, under the zoning regulations, must stand a minimum of 100 feet from each line. Thus the house could not qualfiy as a mosque.

A commission of leading Jews in American life has been formed, under the chairmanship of Arthur J. Goldberg, former Associate Justice of the Supreme Court, to inquire formally into some painful questions left over from World War II. ''Some scholars have argued that neither American Jews nor the United States Government reacted forcefully enough,'' Mr. Goldberg said. ''And there are those who argue that they did all in their power. There has been no definitive study of exactly what took place.''

The Sting, which had finished second in the overall point-standing to the Cosmos in the regular season, succeeded in its first appearance in a Soccer Bowl game. The Cosmos failed for the first time in four. Karl-Heinz Granitza and Rudy Glenn scored for the Sting in the shootout, the league's method of determining a winner in tie games. Vlado Bogicevic was the only Cosmos player to score in the shootout.

ART By MICHIKO KAKUTANI In the penultimate scene of George Bernard Shaw's ''Candida'' the heroine is confronted by the two men who love her, and she recoils from their ultimatum. ''Oh! I am to choose, am I?,'' she exclaims. ''I suppose it is quite settled that I must belong to one or the other.'' Her husband firmly nods, but her you ng lover gets the point. ''She means,'' he explains, ''that she belongs to herself.'' Indeed ''Candida,'' which is now previewing a t the Circle in the Square, portrays the female of the species no t as a passively sweet Victorian lady, but as a strong, independent and thoroughly selfassured woman - an ''unwomanly woman,'' w ho belongs to no one butherself. There are now three major Shavian productions on stage in Manhattan -''Misalliance'' is playin g at the Roundabout Theater, and ''My Fair Lad y'' (which was inspired, of course, by ''Pygmalion'') isat the Uris - and the heroines of these plays not only form a composite por trait of what was known in Shaw's day as the New Woman, but they also betray complicated and frequently contradictory views of women refl ected in both Shaw's life and art.

The United States will embark Thursday on what could eventually be a major change in its government: the return of substantial authority from the Federal to the state level. But there is widespread disagreement across the nation over whether the states will be able to exercise their new powers in a manner acceptable to the American people. State governments, which two decades ago were considered the weakest link in American federalism, have vastly improved both their capacity to govern and their sensitivity to public need, according to government leaders, political scientists and a still-unreleased official stud y of the states made available to The New York Times. Yet, as President Reagan and the vast bureaucracy he heads prepare to give the states a larger voice in deciding priorities and goals of public policy, many authorities on state government say the move faces formidable difficulties, ranging from severe revenue shortages to local officials' deep distrust of their state capitals. States Vary in Capacity These authorities also say that, despite across-the-board reforms in recent years, the states vary greatly in their capacity to carry out services and functions now performed by the Federal Government, with some states weak in some categories and strong in others.

The man who turned a mangrove swamp into Miami Beach in the 1920's also had grand dreads for the tip of Long Island. But his fortune was wiped out after he had finished only three buildings here, and until recently no one else was tempted to pick up where forclosures forced him to leave off. Now, 49 years after Carl Fisher lost control of his properties, developers have purchased his buildings and made plans to renovate them for use as apartments and a motel. Now subdivisions are also on the drawing boards. One of the largest is expected to contain 142 town houses clustered on 67 acres of a 340-acre tract just west of an old military installation called Camp Hero.

Time-sharing, the new rage in vacation real estate, has attracted thousands of satisfied customers across the country. But left strand ed on the beaches and slopes are some unhappy buyers, who in the worst cases, lost all their money. Some 300,000 families, mostly middle and upper income people, have bought time-shares since the concept of purchasing rights to a hotel or apartment unit at a resort for a specific week or two each year was introduced in this country in the late 1960's. After a slow start, the industry began to expand dramatically in the mid-1970's. In the last six years, the number of time-share resorts in the United States has grown from 45 to about 550, according to Carl Burlingame, author of a magazine on time-shares and a book on the subject.