A 14-year-old in San Diego, California, was named the grand prize winner of this year's 3M Young Scientist Challenge, the nation's premier middle school science competition.

Leanne Fan developed Finsen Headphones, a low-cost headphone device that uses machine learning and blue light therapy to detect and treat mid-ear infections in children-potentially preventing up to 60% of hearing loss in children.

As a finalist, Leanne had been assigned a mentor-Dr. Ross Behling, a research specialist in 3M's material laboratory-who worked with her one-on-one to transform her idea from concept to prototype over the summer.

Then, for two days in October, the nine finalists competed at the 3M headquarters in St. Paul, Minnesota, giving their final presentations of their innovations. (Watch her qualifying presentation below…)

The world sees 700 million cases of mid-ear infections and nearly 21,000 deaths annually. Many of those impacted are children in underprivileged populations. Without medical access and or healthcare, diagnosis and treatment are often difficult. Leanne's invention aims to provide an antibiotic free, low-cost option to detect-and treat-any mid-ear infection.

The incoming high school freshman won a $25,000 cash prize, a special destination trip, and the prestigious title of "America's Top Young Scientist". She is planning to use some of the prize money to start the patent process for the headphones.

Public voting in the contest also recognized Harini Venkatesh as this year's Improving Lives Award recipient, honoring the project that has the greatest potential to make a positive impact on the world. Harini's project, The Comptometrist, is a cost-efficient solution that cuts down the time needed to determine myopic power in a patient's eyes. Her prototype would eliminate crowding in clinics, report accurate measures of myopic power in seconds, and closes the window of error in the eye examination process.

The second and third place winners each received a $1,000 prize and a special destination trip. These exceptional students are:

Harini, from Brentwood, New Hampshire, took second place. In third place, Shanza Sami from Iowa City designed a five-stage air pollution filtration device.

Watch Leanne's presentation below – and see other winners this year at youngscientistlab.com…

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