She won $25,000 for her invention. Gitanjali Rao, from Colorado, recently won the Discovery Education 3M Young Scientist Challenge. She has developed a system that tests for lead in water faster than any other device that currently exists. â€œI had been following the Flint, Michigan, issue for about two years,â€? she told ABC News. â€œI was appalled by the number of people affected by lead contamination in water and I wanted to do something to change this.â€?