When she returned to her home village for her father's funeral in 2001, however, she found that many children were not attending school. She decided to stay and open her own private school, which would later become the welfare home that now houses her and her charges.
As public schools were located far from the outlying village, Ban set up the private school in her own home, providing food and lodging for free and charging no tuition.
That year, 56 children attended her school, including orphans, unattended children from broken marriages and migrants' families.
In its heyday, the school had 83 children and two teachers. Ban and the older kids planted crops, raised chickens and pigs and sold farm produce to sustain themselves.
Her illegal school was closed last summer, with all of her students transferred to the nearest public school. But she remains their sole caregiver. Their food alone costs 260,000 yuan a year, and the money largely comes from her own income and donations.
Two years ago, a businessman from northwest China's Shaanxi Province donated over 200,000 yuan, allowing Ban to have a new, two-story home built for the children.
Like a regular family, the children learned to do their share of the housework. Preschoolers helped to mop the floor and older children collected firewood or fed the pigs.
Jiang Shan, 17, volunteered to cook when Ban was busy. "I want to be a chef when I grow up," he said.
Ban offered to care for Jiang and his younger brother in 2007, when his father died and his mother was having a hard time providing for her five children. Jiang, who was 12 at the time, had dropped out of school, but Ban insisted he should continue his education.
Despite widespread respect from local villagers, Ban said she is embarrassed to be running an illegal orphanage.
"I hope the civil affairs authority will declare the welfare home legal," said Ban. "Otherwise, our situation will continue to be really embarrassing."
Figures released by the Ministry of Civil Affairs indicate that China has about 615,000 orphans, although the figure fluctuates every year.
Only 109,000 of these orphans live in government-funded agencies, with the rest cared for by relatives or private orphanages.
Child welfare agencies, however, are extremely few in number. Government-funded agencies total just 406 and the exact number of private welfare homes is unknown.
An additional 58 million left-behind children are being looked after by a single parent, grandparents, distant relatives or neighbors. Either one or both of the children's parents live far from home, seeking work in areas with more opportunity.
'Sister House' case urges efforts in combating corruption in affordable housing