The elderly woman gazes wistfully into the distance, her hands curled over a basket of tobacco, surrounded by the hundreds of cigarettes she has spent hours rolling by hand.

The photograph is one of several snapped by student Rashmitha T in her village in Tamil Nadu, featuring her neighbours who make traditional Indian cigarettes called beedis.

“No-one knows about their work. Their untold stories need to be told,” Rashmitha told the BBC.

Her pictures were featured in a recent exhibition about India’s labourers titled The Unseen Perspective at the Egmore Museum in Chennai.

All the photographs were taken by 40 students from Tamil Nadu’s government-run schools, who documented the lives of their own parents or other adults.

From quarry workers to weavers, welders to tailors, the pictures highlight the diverse, backbreaking work undertaken by the estimated 400 million labourers in India.

Many beedi rollers, for instance, are vulnerable to lung damage and tuberculosis due to their dangerous work, said Rashmitha.

“Their homes reek of tobacco, you cannot stay there long,” she said, adding that her neighbours sit outside their homes for hours rolling beedis.

For every 1,000 cigarettes they roll, they only earn 250 rupees ($2.90; £2.20), she told the BBC.

In the state’s Erode district, Jayaraj S captured a photo of his mother Pazhaniammal at work as a brick maker. She is seen pouring a clay and sand mixture into moulds and shaping bricks by hand.

Jayaraj had to wake up at 2am to snap the picture, because his mother begins working in the middle of the night.

“She has to start early to avoid the afternoon sun,” he said.

It was only when he embarked on his photography project that he truly realised the hardships she has to endure, he added.

“My mother frequently complains of headaches, leg pain, hip pain and sometimes faints,” he said.

In the Madurai district, Gopika Lakshmi M captured her father Muthukrishnan selling goods from an old van.

Her father has to get a dialysis twice a week after he lost a kidney two years ago.

“He drives to nearby villages to sell goods despite being on dialysis,” Lakshmi says.

“We don’t have the luxury of resting at home.”

But despite his serious condition, her father “looked like a hero” as he carried on with his gruelling daily routine, said Gopika.

Taking pictures with a professional camera was not easy initially, but it got easier after months of training with experts, said the students.

“I learned how to shoot at night, adjust shutter speed and aperture,” said Keerthi, who lives in the Tenkasi district.

For her project, Keerthi chose to document the daily life of her mother, Muthulakshmi, who owns a small shop in front of their house.

“Dad is not well, so mum looks after both the shop and the house,” she said. “She wakes up at 4am and works until 11pm.”

Her photos depict her mother’s struggles as she travels long distances via public buses to source goods for her store.

“I wanted to show through photographs what a woman does to improve her children’s lives,” she said.

Mukesh K spent four days with his father, documenting his work at a quarry.

“My father stays here and comes home only once a week,” he said.

Mukesh’s father works from 3am till noon, and after a brief rest, works from 3pm to 7pm. He earns a meagre sum of about 500 rupees a day.

“There are no beds or mattresses in their room. My father sleeps on empty cardboard boxes in the quarry,” he said. “He suffered a sunstroke last year because he was working under the hot sun.”

The students, aged 13 to 17, are learning various art forms, including photography, as part of an initiative by the Tamil Nadu School education department.

“The idea is to make students socially responsible,” said Muthamizh Kalaivizhi, state lead of Holistic Development programme in Tamil Nadu’s government schools and founder of non-government organisation Neelam Foundation.

“They documented the working people around them. Understanding their lives is the beginning of social change,” he added.

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