Self-taught engineer Kelvin Doe (THNKR)

The youngest person ever to be invited to the prestigious Massachusetts Institute of Technology's Visiting Practitioners Program is a 15-year-old self-taught engineer from Sierra Leone named Kelvin Doe.

In a town where electricity is available generally only once a week, Kelvin taught himself to build batteries and generators, as well as a transmitter for his own community-empowerment radio station, using discarded electronics that he found in the neighborhood's garbage cans.

Watch his triumphs and his struggles as he travels to the U.S. for the first time to attend the program.