Chennai, Jan. 1: From a small laboratory in a Nagercoil school to the biggest platform for the country’s scientists, K. Masha Nazeem has come a long way.

The Class VIII student, who designed a novel hygienic device for Indian trains, has been invited to the 93rd Indian Science Congress to be held in Hyderabad from January 3 to 7.

Masha’s invention ? a drainage disposal system ? would ensure station tracks are not soiled. The device allows a train driver to switch off the discharge of waste from toilets when a train enters a station and switch it on as it leaves the platform.

“This is godsend for my daughter, a recognition of her talent and something for Tamil Nadu to be proud of,” said a visibly excited N. Kaja Nazeemudeen, Masha’s father, at their Nagercoil home in Kanyakumari district.

Masha has been asked to explain her device to top-level scientists from across India, who will select the best models from among the exhibits to be sent to the International Science Exhibition, Nazeemudeen said. President A.P.J. Abdul Kalam is scheduled to be present at the Hyderabad meet, he added.

The 12-year-old was playing with junk car parts when she hit upon the solution to one of India’s most vexing problems. But her eureka moment did not last long.

After her first break at the Southern India Science Fair in January 2005 held in Secunderabad, where her device won the first prize, Masha has had a bumpy ride.

The schoolgirl had set her sights on the National Level Exhibition in Raipur, but not winning any prize at the State Level School Science Exhibition held earlier posed a hurdle to her dream.

But Masha’s perseverance paid off and she got an audience with the President ? also a scientist ? who applauded her effort and advised her to apply for a patent for her device.