Sok Jakrea, a high-school senior, knows a fair bit about the starvation and torture that the Khmer Rouge inflicted on her country. None of it is first-hand: She was born five years after the regime's collapse. The stories come from her parents, who lived through one of the darkest chapters of Asian history.
"It was very difficult for them to live in that time," Ms. Sok says, resting between classes in a dusty schoolyard. "It's good for students to know about the history of Cambodia, but they don't want to know about the bad things."
In the next-door classroom, history teacher Sim Pharoeun is setting a test for her class of more than 50 seniors. The test covers world history - so far she hasn't touched on the bloody Khmer Rouge period of 1975-79.
One reason for her reluctance is that she doesn't have a textbook - the education ministry recalled it last April after complaints over accuracy. The textbook was the first in a decade to add Khmer Rouge to the 12th-grade history syllabus, and teachers haven't yet been issued an updated version.
But the recall is part of a deeper struggle in Cambodia to even begin to address its bloody legacy, let alone reach a consensus on what happened and why. Other Asian nations have also found it hard to face shameful periods of their history - notably Japan's denial of wartime atrocities. But Cambodia's pain arguably cuts deeper: The Khmer Rouge committed genocide against their own people.
Unless the next generation is educated, some observers say, history could repeat itself. People born after the Khmer Rouge now outnumber survivors of the genocide. Others, like Ms. Sim, argue that it's still too soon to understand the atrocities.
"The government doesn't want us to teach this history, because you see we haven't yet discovered the full meaning of the political ideology of the Khmer Rouge. Maybe in the future we will find a fuller meaning, so our current teaching could be wrong," she says.
Some Cambodians believe that this "fuller meaning" requires a tribunal to prosecute former Khmer Rouge leaders accused of genocide and crimes against humanity. Between 1975 and 1979, an estimated 1.7 million people died of starvation, execution, and overwork under the regime.
Last month, Cambodia and the United Nations revived talks in New York about Cambodia's proposal to create a domestic war-crimes tribunal. Last year, the UN broke off similar talks after years of painstaking negotiations, citing concerns over whether Cambodia is capable of holding a fair trial that meets international standards. No decision was reached during the recent talks.
Advocates of a trial say it would create a historical record for future generations and help survivors of the genocide come to terms with their losses. "Many of us find it difficult to move on without any answers. I think that the tribunal will set us free," says Youk Chhang, director of the independent Documentation Center of Cambodia.
But on the streets of Phnom Penh, which the Khmer Rouge evacuated in 1975 as part of an effort to turn the entire country into an agrarian commune, reactions are mixed. Some fear stirring up political tensions here after years of relative stability. Others say they prefer to focus on the future.
For many of these young Cambodians, the "Killing Fields" - a 1984 Hollywood film about an American journalist in Cambodia during the Khmer Rouge - is no more compelling than any other DVD sold in the city's bustling markets. "I don't think we need to review this history. It happened in the past, and we don't need to look back," says Von Chantas, a high school senior.
Still, for every person ready to forget, others are hungry to learn. Mr. Youk says he often gets visits from seniors who've picked up snippets in class or at home and want to find out more.
"We're the younger generation and we've been told stories by our parents, so we want to know for sure what happened during the Khmer Rouge time," says 15-year-old Som Kimheang.
In the past decade, most educators in Cambodia have settled on silence as the easiest option. Then in late 2001, the education ministry decided to include a new section on the Khmer Rouge in 12th-grade social-sciences textbooks, reversing an old policy.
That ray of light appeared to end only a few months later. Politicians accused the government of a biased account of the 1993 general election, a turning point in modern Cambodia, and the book was recalled. Now officials say they are working on an updated edition, but refuse to say when it will be completed. Teachers say they have no choice but to strike this period from classes.
Copies of the book missing the final chapter mysteriously are on sale in bookstores in Phnom Penh, even though the education ministry says it hasn't issued a new version.
Chhut Sereyrum, a member of the committee that drafted the 2001 textbook, admits that their historical account leaves many unanswered questions, including how some Khmer Rouge leaders were never prosecuted and others are even prospering today in parts of rural Cambodia as well as the capital.
The answer, he says, is to hold a war-crimes tribunal and lay the ghosts to rest. "It's very important to teach our children about history. But if we don't have a trial of the Khmer Rouge, it's very difficult to teach this history because some of them are still in power. If you say something careless, it could be dangerous," he says.
To Youk, who has amassed 800,000 documents in his archive, such excuses don't hold, given the wealth of evidence against the Khmer Rouge. He says teachers in some schools are covering this period anyway, often using supplementary texts such as survivors' accounts of their suffering.
Instead of waiting for a state-sanctioned tribunal, committee members should be busy conducting research for their textbooks, he says. "They don't understand the difference between history and propaganda."