|The head of the impoverished household during the week is a malnourished 14-year-old girl, Dao Ngoc Phung. She's tiny, standing just 4 feet 11 inches and weighing 97 pounds.
Yet if Phung is achingly fragile, she's also breathtakingly strong. You appreciate the challenges that America faces in global competitiveness when you learn that Phung is so obsessed with schoolwork that she sets her alarm for 3 a.m. each day.
The children's mother died of cancer a year ago, leaving the family with $1,500 in debts. Their father, a carpenter named Dao Van Hiep, loves his children and is desperate for them to get an education, but he has taken city jobs so that he can pay down the debt. Therefore, during the week, Phung is like a single mother who happens to be in the ninth grade.
Phung wakes her brother and sister, and then after breakfast they all trundle off to school. For Phung, that means a 90-minute bicycle ride each way. She arrives at school 20 minutes early to be sure she's not late.
After school, the three children go fishing to get something to eat for dinner. Phung reserves unpleasant chores, like cleaning the toilet, for herself, but she does not hesitate to discipline her younger brother, Tien, 9, or sister, Huong, 12. When Tien disobeyed her by hanging out with some bad boys, she thrashed him with a stick.
Most of the time, though, she"s gentle, especially when Tien misses his mother. "I try to comfort him," she says, "but then all three of us end up crying."
Phung yearns to attend university and become an accountant. It's an almost impossible dream for a village girl. Phung pleads with her father to pay for extra tutoring in math and English. He explains softly that the cost - $40 a year - is unaffordable.
(For anyone who wants to help Phung, an aid group called Room to Read has set up a fund to help her and girls like her; details are on my blog, nytimes.com/ontheground, or on Facebook.com/Kristof.)
I wish we Americans could absorb a dollop of Phung's reverence for education. The United States, once the world leader in high school and college attendance, has lagged in both since the 1970s.