Gitanjali Rao is "America's Top Young Scientist." She earned the title as the winner of the Discovery Education 3M (MMM) Young Scientist Challenge. 

The 11-year-old Colorado native developed a portable sensor-based device that can detect lead in water, faster than other existing methods.

She showed us a prototype of the testing kit. It sends results to a smartphone app, which Gitanjali also developed.

The competition gave Gitanjali the opportunity to work with 3M scientist. She was also paired up with a mentor, Dr. Kathleen Shafer.

This is the tenth year for the Discovery Education 3M Young Scientist Challenge. In that time it awarded hundreds of thousands of dollars to innovative students.

Gitanjali received a $25,000 prize, while the remaining finalists each received $1,000.

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