Elon Musk, the billionaire Tesla founder, invests in cars, rockets and tunnels and hopes to colonise Mars, but he has one venture that he has kept secret at his SpaceX campus.
He has founded a school called Ad Astra, at his offices in Hawthorne, California, dedicated
to child geniuses.
Unlike other schools in the United States, its loose curriculum focuses on projects that most fascinate the entrepreneur, from artificial intelligence and machine ethics to robotics and coding.
Musk founded the experimental school three years ago to "exceed traditional school metrics on all relevant subject matter through unique project-based learning experiences", according to a regulatory filing document discovered by the tech website Ars Technica.
Ad Astra has been kept secret as a mostly private venture. It educates children aged from 7 to 14 and started with a class of eight, including Musk's children. It has grown to around 40 students made up of gifted applicants and the children of SpaceX employees.
According to the filing, the school is funded entirely by Musk. The document reveals that the school emphasises "ability over age" for group projects, with study of science, maths, engineering and ethics.
It adds the school will develop "remarkable people imbued with a strong sense of justice".