Garvanza Elementary School in Highland Park is celebrating its 100th anniversary this week, a milestone in a history that reflects Los Angeles'.

But the anniversary is not quite as simple as one would think.

The school is actually 115 years old, having been founded in 1885 when the village of Garvanza was an outpost beyond the city limits.

The main building on the campus is indeed old, but not 100. It dates to 1937, a faintly Art Deco product of the Depression-era building program with which the Roosevelt administration sought to stimulate a national recovery.

In all, there have been four Garvanza schools, all recorded in photographs that will be on display at Friday's event. The first was the classic American one-room schoolhouse with a steeple.

That was followed about 1900 by a three-story Victorian with a campanile. The change in scale gives testimony to the rapid growth of the Arroyo Seco community during the real estate boom of the 1880s and '90s.

A four-story Tudor followed in the mid-1920s, only to be knocked out by the 1933 Long Beach earthquake.

The only constant in all these structures is the location: All four Garvanzas have been at the spot that today is known as 317 N. Avenue 62.

The somewhat artificial excuse for a centenary celebration is the annexation of Garvanza into Los Angeles, and thus into the city school district, in 1899.

The fact that Garvanza was one of the first suburbs of a city incorporated in 1850 is a clue that the school is far from the oldest in the Los Angeles Unified School District.

According to the district's "History of Schools," a dog-eared volume compiled in 1972, Los Angeles Unified had 63 schools before 1900.

The oldest, Spring Street School, was built in 1855. But it's no longer around. Today The Times' building stands on the site of the former campus at 2nd and Spring streets.

Spring Street School was one of 32 pre-1900 schools that later disappeared--the building and campus obliterated by the city's growth and metamorphosis.

Of the 31 19th century schools that still hold their ground, Garvanza is one of the earliest. Going by its actual opening in 1885, only six schools are older. One other, Weemes Elementary in South Los Angeles, is also 100 this year. The longest surviving school is San Pedro Elementary, founded in 1866.