"I had been following the Flint, Michigan, issue for about two years," Rao told ABC News. "I was appalled by the number of people affected by lead contamination in water and I wanted to do something to change this."
The seventh-grader watched her parents try to test the water in their own home and saw how difficult it was. Rao, who browses the MIT Department of Materials Science and Engineering’s website every week to see "if there’s anything new," found an article on the site that detailed how new technologies are used to detect hazardous substances. She figured these technologies could be adapted to detect lead.
With the help of her parents, teachers, and experts at local colleges and universities, Rao worked on her project in local college labs and a "science room" she has in her own home.
“I have a room with green walls and black polka dots and a huge white table for all my experiments," said Rao. "Most of my code was done there. Most of the spills and failures were made there."
Earlier this year, Rao was named one of 10 finalists in the 2017 Discovery Education 3M Young Scientist Challenge. She partnered with a 3M scientist who helped her develop her lead detector. The final result was Tethys, a device that uses carbon nanotube sensors to detect lead in water. It's faster-acting and more efficient than similar devices that are currently on the market.
This week, Rao presented Tethys to a panel of judges in St. Paul, Minnesota. She won the Discovery Education 3M Young Scientist Challenge's grand prize, which came with a $25,000 check.
"It's not hyperbole to say she really blew us out of the water," said Dr. Brian Barnhart, one of the seven 3M judges. "The other nine kids, they were also such amazing kids, so for her to stand out the way she did with a peer group like this is like an exclamation point on top of it."
Rao says her goal is "to save lives and make the world a better place." It's safe to say she's already well on her way.