It was recess yesterday with no playground at Peking's only American school, so four pupils, a little less than half the student body, joined their principal in a romp down icy city streets on roller skates.

One way or another, a few imaginative Americans like school principal Evie Sylvester have made their lives tolerable in this crowded but barren city. But now a new era has begun. The soon-to-be-designated U.S. embassy is expected to double in size, bits of Americana like CocaCola and Charlie Chaplin movies are seeping in, and longtime residents wonder if it might be Peking's turn to adjust.

According to chief U.S. envoy Leonard Woodcock, the normalization of Sino-American relations that began Monday will allow the juggernauts of Washington bureaucracy -- Commerce, Defense, Agriculture, Treasury -- to open offices here. U.S. businessmen, students and journalists will be arriving in waves. A tiny American colony of little more than 100 people should expand to several times its size.

Will this kill the charm of lod, isolated Peking? Sylvester, whose husband is a senior State Department officer here, doesn't think so. "I came here in 1976. And just taking television in the last tweo years, there is so much more you can see now. I don't think you can kill charm that may not have been there before."

In the great social and political thaw that has taken place since the death of Chariman Mao Tse-tung in 1976, the number of plays, ballets, comedies and foreign films appeasring in Chinese theaters and on Chinese television has mushroomed. "CocaCola will soon be on sale, European booze just went on slae," said one happy American describing yhe g radual lubrication of this very dry, dusty city.

Yet longtime residents say growing pains are inevitable as this town of generally reserved and well-behaved people adjusts to a sudden influx of ofter-undisciplined Americans bent on bringing some of their own culture to China. Dancing and disco music, all the rage here now, barely squeaked through a vehement attack by Chinese dogmatists a few weeks back. Last-minute support from musicloving Africans and Latin Americans, whose Third-WORLD OPINIONS CARRY GREAT WEIGHT, SAVED HIP-WIGGLING FROM POLITICAL LIMBO, BUT GOLF OR THE BIKINI MAY NOT BE SO FORTUNATE.

@U.S. officials here a re also battling a space problemm as their relatively small liaison office building and nearby annex provide barely enough room for the 35 officers and employes already here. Officials say they would like to construct a new, larger building, but Woodcock said no formal request has been made to the Chinese yet. The Yugoslav government, another of China's new international friends, has been asking for bigger embassy quarters for a year with little success. New apartments for foreign residents are also very scarce.

The school for American children here occupies about three tiny rooms in the American diplomatic office annex, once a Romanian trade delegation office. There are nine pupils now, soon to expand to 13, but businessmen and officials report dozens more families are coming with children who will need a school. Many families now send children to Chinese schools or back to the States.

Sylvester, who supplies her own roller skates and has taught all her older pupils to use them, finds the daily exercise a use them, finds the daily exercise a refreshing change for children who have a few recreation outlets during Peking's bitter cold winter. "The People's Liberation Army guards enjoy watching us." she said.

Individualized attention in the tiny school also accelerates learning, but Sylvester says the school must now look for larger quarters to prepare for the expected a rrival of many new students.

Relaxation of political controls in Chines society has also increased the demands on U.S. officials here. The number of applications from Chinese to join relatives living in the United States was 500 in November and 1,000 in December.

There were no where near that many before China announced, early in 1978, that it was loosening restrictions on emigration in order to win the good will of overseas Chinese in the United States and other parts of the world.

The liaison office does not officially become an embassy until March 1, but Washington's recognition of Peking Monday opens the way immediately to more wide-ranging direct contacts with Chinese officials in trade and industry ministries.

Until new embassy quarters are built or assigned, however, the only visible sign of the new official American status here will be a new name plaque on the office's 6-year-old office building and a new display board. The Chinese until now had forbidden the Americans to put up a board outside for Chinese passersby to view pictures of American life and progress, something most other embassies here have done to promote their own countries. "I don't know what we'll put up there," said one official. "Maybe scenes from 'Deep Throat.'"

Despite increasing cultural opportunities, Americans living here still often find themselves at a loss for evenuing entertainment. Charlie Chaplin's "Modern Times" and a Technicolor version of "The Hunchback of Notre Dame" just opened here. There are parties to go to or antiques to collect, but many foreigners here still find the city, with its constant gloomy haze of winter dust, very depressing.

In order to, in the words of one American woman, "cut down on the suicidal tendencies" of Foreign Service officers' wives, the liaison office has hired many women as clerks and teachers. They have helped solve a serious staff shortage and will probably be needed in greater numbers as the embassy expands, one official said.

Although the Chinese had said little about how they plan to solve the housing shortage aggravated by the influx of dozens of Americans, there are reports that a large office complex for U.S. construction officials, airline and hotel agents is now under construction.

The information department of the Foreign Ministry has also received applications from more than 60 American news organizations for permanent bureaus here. Chinese officials say they expect permission for 15 to 20 such bureaus will be granted, but that it may might take a long time to provide proper facilities for them.

Longtime residents who have seen some nervous breakdowns and embarrassing behavior by Americans trying to adjust to life here say they await the new influx with interest. One said he hoped newcomers would remember the case of the U.S. Marine guard contingent, which was ejected by the Chinese after a few drunken parties and some marching with full battle packs through Chinese parks.