IF YOU'RE looking for a way to bring this country's history into focus for your children, you're in the right town. Historic homes, original archives and re-creations of arms, forts, mills, blacksmiths and shops abound.

But for an extraordinary way to experience the past, visit National Cemetery in Arlington, where the nation honors those who served it. Each of the nearly 200,000 tombstones serves as a piece of the puzzle that is American history.

Anyone who's made it through a high school American history course should have no trouble remembering some of those interred there. Sharing your memories of figures who peopled your textbooks can be a wonderfully low-key way to share a respect for the past with your kids.

Often, the nation's respect is evidenced with the most solemn kind of pageantry. An average of 14 funerals occur each day at National Cemetery, and in a trip there you may run across one of the horse-drawn caissons used for full-honors funerals.

But a surefire way to pick up the pageantry is to head immediately to the Tomb of the Unknown Soldier. In a large granite sarcophagus lies the body of an American soldier who served in France in World War I. Unknowns from World War II and the Korean and Vietnam conflicts lie beneath the white stones in front.

The soldiers guarding the tomb go through a rigorous selection process "and are really the creme de la creme," says cemetery historian Kerri Childress.

"They look at height, test scores, your general background -- you have to get White House clearance," explains Specialist John Vankan, one of the guards, "and body shape." The shape they're looking for is slender: The men (this is considered a combat position, so no women are allowed) wear 29-inch belts, which pull so tightly around their midriffs that it takes another person to finish dressing them.

The thing to remember watching the guards on duty is the number 21, symbolizing the highest salute in military ceremonies -- as in the 21-gun salute. They cross their walkway in 21 steps, watch the tomb for 21 seconds, turn and walk the other way another 21 steps.

In front of the Tomb is the Memorial Amphitheater, where most state ceremonials at the park are held. A quick stroll across it brings you to another part of our past -- the Spanish American War. Remember the Maine? Part of its mast is there, and 229 who died in that disaster (167 of them unknown) are interred around it.

Lying in a sarcophagus at the foot of the mast (though not buried underground, since he wasn't a U.S. citizen) is composer Ignace Jan Paderewski, president of the Polish legislative assembly immediately before its Nazi takeover in World War II. He asked that his remains be returned to his homeland when Poland was free, "but the Communists took over when the Nazis left," Childress explains, "so he's still waiting."

The Unknown Soldier is the most visited stop, Childress says, but most people also stop by the grave of John F. Kennedy, which lies on a hill beneath Arlington House mansion, within sight of a memorial to another of America's assassinated presidents, Abraham Lincoln.

Kennedy's brother Robert lies a short walk away. But the Kennedys aren't the only presidential family represented here. President and Mrs. William Howard Taft are buried close to where Robert Lincoln, the only one of Abraham's children to reach adulthood, is interred.

The custom of burying the military dead on the Arlington grounds started during Lincoln's administration, on the advice of Gen. Montgomery Meigs, quartermaster general of the (Union) Army and an old friend of Robert E. Lee, whose family had a home there.

"Meigs was infuriated by Lee's decision to leave the Union," Childress says, "and wanted to make sure that Lee would never want to return to the house."

So when Meigs was ordered to find a place to bury the vast numbers of soldiers dying from disease and battle wounds in the Civil War -- the total interred eventually reached 17,000 -- "he only submitted one name: the Arlington estate," Childress says, "and started burying bodies around the edge of Mrs. Lee's rose garden."

Mary Custis Lee, Robert's wife, inherited Arlington House and its surrounding 1,100 acres from her father, George Washington Parke Custis, grandson to Martha Washington by her first marriage and foster son to the general himself.

The house -- a brick structure built largely without benefit of a mason and stuccoed over -- was started with the north wing in 1802 but not completed until 1818, says Agnes Mullins, curator at Arlington House. Today, it's open for tourists who are introduced to the house by a guide in 19th-century dress, and invited to continue on a self-guided tour. Among the rooms open to view are the family parlor where Mary and Robert were married and their bedroom upstairs.

Their seven children lived in what Mullins calls fairly spare bedrooms on the same floor: "Gen. Lee thought all a bedroom needed was a bed, a chair and a washstand," she says. They did manage to gather a few more things into their rooms -- including a tiny enclave full of dolls and toys that children enjoy looking at -- but the rooms were inspected by the general with "the white glove treatment," Mullins reports.

Mrs. Lee had fallen ill with what Mullins believes was "rheumatoid arthritis in 1825, a condition greatly intensified by the time the war began. She spent the bulk of her day headquartered in a first-floor room that is now filled with paintings of Washington's military campaigns done by her father. In that room, Mrs. Lee supervised the final packing before the Lees moved out forever, glancing out the window occasionally towards the Long Bridge to see if Union soldiers were coming to occupy the house.

Neither General nor Mrs. Lee ever returned to the house after the war, though the general passed by it on his way to testify before Congress and saw its columns gleaming in the sunlight, and Mrs. Lee drove up to the door once to talk with her People.

That's what she called the Custis family slaves, who were taught to read and write -- against Virginia law. "The motive was to save their souls," Mullins says, explaining that the lessons mainly occurred during Sunday School.

During and for almost thirty years after the war, Arlington hosted an experiment dedicated to the practicalities of emancipating slaves. A "Freedman's Village" -- eventually home to between 1,500 and 3,000 "contrabands," or freed slaves -- was erected, first as a tent city along what is now Section 25, near Eisenhower Drive, then as a wooden village on the hill.

The village had two schools, a hospital, an orphanage, an old-age home and houses and gardens. Villagers strugged to make the transition to the life of freedom by tending the plot of land each was given, learning trades, raising crops and becoming literate. The black abolitionist Sojourner Truth served as a counselor there, often to the dismay of nearby residents, whom she fought for her rights and the rights of the village residents.

No trace of Freedman's Village remains, but perhaps the best reminder of the continuing cost of the freedom it was designed to promote can be found in Section 36. There lies Medgar Evers, the civil rights worker gunned down in 1963 -- another man and moment from the past that have shaped the present. ARLINGTON CEMETERY

Arlington National Cemetery lies at the Virginia end of Memorial Bridge, and can also be reached off the George Washington Parkway. Entry to the cemetery and Arlington House is free. Cemetery hours through September are 8 a.m. to 7 p.m., and to 5 p.m. October through March.

Arlington House canbe reached on foot or by Tourmobile (for a fee). It's open 9:30 a.m. to 4:30 p.m. starting in October.

For more information, phone the cemetery at 697-2131 or Arlington House at 557-0613. HISTORY IN STONE

Visitors can look up graves by using the grid map available at the information booth next to the parking lot. A brochure, also available there, lists the graves of many of its famous people. Here's a sampling:

WILLIAM JENNINGS BRYAN -- Presidential candidate and anti-evolution lawyer at the Scopes trial, Section 4, Lot 3118-3131, Grids YZ-11.

ADMIRAL RICHARD E. BYRD -- Polar explorer, Section 2, Grave 4969-1, Grids WX-32.

JOHN FOSTER DULLES -- Secretary of state under Eisenhower, Section 21, Grave 6-31, Grids M-20.

VIRGIL I. (GUS) GRISSOM -- Astronaut, Section 3, Grave 2503-E, Grids Q-15.

OLIVER WENDELL HOLMES -- Supreme Court Justice, Section 5, Lot 7004-8, Grids VW-36.

ROBERT TODD LINCOLN -- son of Abraham Lincoln, Section 31, Lot 13, Grids Y-38.

IRAN MEMORIAL -- to the failed Iranian hostage rescue mission, between the mast of the Maine and the Memorial Amphitheater.

ROBERT E. PEARY -- Arctic explorer, Section 8, Lot S-15, Grids X-8.

PRESIDENT & MRS. WILLIAM H. TAFT -- Section 30, Grave S-14, Grids YZ-39 1/2.