Turkish-American groups have lobbied schools to include materials that question whether the 1915 killings were, in fact, a genocide.

Historians have concluded that more than one million Armenians were killed in 1915, and contemporaneous reports from newspapers and foreign embassies often called the killings "systematic."

The International Association of Genocide Scholars affirmed in 2005 that the killings were a genocide.

The Turkish government claims the death toll is far lower, and that the killings were part of broader civil unrest, not a planned extermination.

Labelling the Armenian genocide has long been a touchy subject in the US. The foreign affairs committee of the US house of representatives voted narrowly earlier this year to declare the killings a genocide, a move that prompted Turkey to recall its ambassador to the US.

Massachusetts has one of the largest Armenian populations in the US.