A year ago MTSN Rukoh school was a dark and eerie place, deserted and caked with foul black mud. On every wall, there was a tide mark seven feet high where the tsunami waters reached.
Within a week, 40 volunteers for the aid agency Concern had helped to clean it up. Now the corridors echo with the sound of children. But no one can forget the disaster.
Rukoh is in Indonesia's Aceh province, one of the areas hardest hit by the tsunami. Nearly 41,000 children perished. Thousands more lost one or both parents; 2,500 teachers are dead or missing and more than 2,000 schools destroyed or damaged.
"Every single child is affected one way or another," says Sayo Aoki, Unicef's education officer in Banda Aceh, the state capital.
An earthquake registering 8.7 on the Richter scale shook the area on March 28. In Aceh, seismic standards have now been changed.
Schools can be "built back better", many of them to quake-proof standards.
Even temporary schools have stronger foundations to protect against earthquakes.
"It is now recognised that it is a very active area for earthquakes," said Ms Aoki.
There is a new focus on emergency preparedness in schools.
"Teachers and pupils feel a need to know how to react in a disaster situation. They feel very strongly that if they had known more, they could have saved others," she said.
The Canadian Red Cross notes in its year-on assessment that disaster preparedness was low all over the region, contributing to the high death toll.
"Preparedness training starts by identifying the risks. Are the stairs too narrow? Where to meet up? Where is the open ground? - simple evacuation drills and response plans," said Ms Aoki.
The provincial education department is leading a training initiative with emergency preparedness brochures, cartoons and written explanations.
Unicef has also prepared a mini-series of animation video and picture story books for Years 1-6.
"We will adapt them for local needs, collect and use people's local experiences, and make it more effective," she said.
"Knowing what to do next time helps children feel in control," said Susan Nicolai, Save the Children's emergency education adviser.
Talking about the disaster and what to do in future has been an essential part of coping and helps children to understand what has happened, while stressing that the tsunami was probably a once-in-a-lifetime event.
"Often children think the tsunami came because they were bad.
"Part of emergency preparedness is to reassure them and explain what they can do," said Ms Aoki.
* Image from Children of the Tsunami: Khao Lak - a Story of Hope edited by Robin Nagy (Sirivatana Interprint)