Beijing resident Yan Minwen, 76, spends more than 12 hours each weekend traveling to and from a village in neighboring Hebei province to give private lessons to children left in their grandparents' care.

Yan began visiting Xiguanzhuang village, about 100 kilometers southwest of the capital, in March and hasn't skipped a week apart from the summer school holiday.

"I want to do something useful during retirement, and tutoring children in rural areas who lack home instruction is a good option," Yan said.

Xiguanzhuang, in Baoding's Laishui county, was the home of Yan's grandparents, and their residential land was passed on to her when they died.

On occasional visits to the village she learned that most of its young parents had gone to big cities as migrant workers to make a living, leaving their children under the care of grandparents.

"The children need instruction at home but most of their grandparents are illiterate and don't know how to help in children's education," Yan said.

Yan studied at university and tutored her own daughter, and wanted to use that experience to do something to help.

She borrowed a room in her uncle's home in Xiguanzhuang and put some secondhand desks in it. The first students began using them on March 23.

Yan leaves her home in Beijing's Wangjing area at 9 am every Friday and arrives at the village around 3:30 pm after more than six hours on four different buses.

"The first two buses in Beijing are free for elderly people like me and the other two cost me a total of 11 yuan ($1.60)," Yan said.

On Friday night and Saturday, about 25 pupils gather in the room to study and do homework under Yan's guidance.

"I don't give specific lessons but instead create a good atmosphere for pupils to study and help them solve problems in homework," she said.

The children are from different grades, ranging from primary to middle school.

"I can help deal with most of their questions in English and mathematics, but I have forgotten the knowledge of other subjects like chemistry and physics," she said. "But I still have the ability to learn."

Yan also gives psychological guidance to the children.

Tang Jia, a third-grade middle school student, felt under pressure before the high school entrance examination. Her mother quit her job and returned to the village to support Tang, but without much education she didn't know how to help.

She learned about Yan's study group and took her daughter along to ask for help at the end of March.

"Based on the experiences of my daughter and I in exams, I told her how to prepare for them under a good psychological state and that she should give more attention to subjects she was not good at," Yan said.

Two hours of guidance from Yan made Tang more confident and helped her achieve a good result in the exam two months later.

Yan was an automation major at the University of Science and Technology Beijing from 1960 to 1965. After graduation, she became an equipment operator at a company making aluminum products.

"Now my time is divided between tutoring private pupils in the village and teaching automation in vocational colleges in Beijing, which includes online classes and face-to-face classes," Yan said.

She began teaching part-time at vocational colleges after retiring in 1997.

Yan said some of her elderly friends had told her that her retirement seemed tiring.

"It's sometimes physically tiring, but I feel it is more fulfilling," Yan said. "If I didn't do these things, I would feel the loneliness and pain all the time after losing my husband."

Yan's husband died of pneumonia in August last year. "It was the two of us who wanted to instruct village pupils when we saw a similar case on TV in 2015," she said.

After her husband died, her daughter encouraged her to travel as a way to ease the pain. But Yan said the only thing she wanted to do was to go back to her ancestral home to fulfill the dream she shared with her husband.

When the study group started in March, there were only 10 pupils in the room which measures less than 10 square meters. But the number of pupils can now reach close to 30, making the room crowded.

"With the number of pupils increasing, I plan to build a house on my grandparents' residential land that can hold at least 40 pupils," Yan said.

She has already drawn a sketch of the house and plans to spend about 100,000 yuan from her savings and pension to build it.

"Other old people may find traveling a good choice after retirement," Yan said. "Well, I have found my own way toward happiness in later life."