Mount Merapi spewed streams of lava and clouds of gases, raising fears of another major eruption, while hundreds of Indonesian children attended classes under tents Monday in nearby areas devastated by the recent earthquake.
The volcano has been erupting for months, but activity has increased since the 6.3-magnitude quake struck central Java island on May 27, killing at least 5,857 people.
The government revised its death toll downward from more than 6,200 after determining that some victims had been counted twice and others initially believed dead were found alive.
While lava poured down the mountain's southwestern slope Monday, the Indonesian government stepped up relief efforts for quake victims, sending some 200 truckloads of rice to hard-hit areas to help the more than half million people left homeless.
The quake damaged or destroyed more than 130,000 homes and at least 835 schools, the U.N. children's agency and government officials said.
But on Monday, at least 10 damaged schools held end-of-year exams for eighth-grade students in tents, the agency said.
"The pupils are not as cheerful as they used to be," said Nuroh Hidayutun, the head teacher at one of the schools in Serut, as 15 pupils puzzled over math problems in a tent. "But keeping up the routine is important."
Across the road, volunteers sang songs with about 35 kindergarten students and gave them drawing lessons.
"There is nothing left of our house, so this entertainment is invaluable," said Aminiah, who came to pick up her two children. Like many Indonesians, she uses only one name.
About a third of the estimated 647,000 people displaced by the disaster are living in makeshift shelters — often just plastic tarps — with no toilets or running water, surviving on donated food.
Aid agencies stepped up supplies of clean water and latrines but warned that unsanitary conditions could lead to a wave of diarrhea and skin diseases, as well as infections.
Some 200 trucks, each filled with more than four tons of rice destined for the disaster zone, left the city square in the ancient royal capital of Yogyakarta.
"The government will ensure everybody gets food," Vice President Yusuf Kalla said, seeing off the trucks.
He promised the government would provide each survivor with 22 pounds of rice monthly until houses are rebuilt.
The international relief effort has picked up pace in recent days, although aid has yet to reach some remote areas. The United Nations has appealed for $103 million for recovery efforts over the next six months.
The epicenter of the powerful quake was about 50 miles south of the rumbling Merapi, one of the world's most active volcanos, and its activity has increased in recent days.
Merapi's lava dome has swelled since the quake to 330 feet, raising fears it could collapse, officials said. That could send clouds of gas and searing-hot debris pouring down toward thousands of people living on its fertile slopes, the government warned.
The authorities ordered residents in a danger zone to evacuate, but many refused to abandon their livestock and crops.
Indonesia is prone to seismic upheaval because of its location on the so-called Pacific "Ring of Fire," an arc of volcanoes and fault lines encircling the Pacific Basin.