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.

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