When the Spanish cultural center in downtown Mexico City wanted to expand, excavations uncovered a Smith & Wesson revolver, a partial figurine of Jesus – and the ruins of an ancient Aztec school. The school, called the Calmecac or "house of the lineage" in the Aztec language of Nahuatl, was unearthed in what was once the heart of the Aztec empire, Tenochtitlan, now a dizzying slice of the megalopolis of Mexico's capital. The ruins went on display for the first time in a recently opened exhibit in the cultural center's new wing.

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The school, built between 1486 and 1502, was a sacred place of study for the children of Aztec nobility.

And though commoners inside the school walls would have been few and far between, the Aztecs of central Mexico played an important role in the world of education.

They are believed to be among the first to offer universal education at a time when other societies reserved study only for the privileged.

“All Aztec children went to school,” says Harry Patrinos, the lead education economist at the World Bank. “It all disappeared after the [Spanish] conquest, and it took a long time before the colonies had any education system.”

FULL STORY: All Aztecs went to school? A lesson for Mexico. – CSMonitor.com.