Education startup MasterClass announced today that it has scored a $15 million investment led by New Enterprise Associates. NEA partner Rick Yang will join the board at MasterClass.

The company offers on-demand classes taught by celebrity instructors like Serena Williams, Kevin Spacey, Christina Aguilera, and Usher (an investor). Each class, the startup says, is tailored by the instructor to “reflect their own unique approach to their craft.”

Class packages start at $90 and include 10-25 video lessons and any class materials.

“This as close to a private lesson with me as you can get,” says Williams in her introduction video.

“We’re continually developing and refining our style of online class where you get into the minds of the world’s best and learn to see with their eyes,” said MasterClass’ cofounder and CTO Aaron Rasmussen.

“This new round of funding gives us fuel to capture and create more classes with new, innovative methods,” he added.

MasterClass has raised at least $21.4 million in funding, to date. Other investors include Javelin Venture Partners, Harrison Metal, and Bloomberg Beta.

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