The interactive portion of the day will feature panel discussions as well as booths featuring "new technology and innovations", though the details on both aren't too concrete yet. The White House says that the panels will include topics like "how to make change stick with organizers who are having an impact, as well as a discussion with influencers who are using their platforms to bring about positive change."
The notion of change and inspiration appears to be the theme of the day -- the musicians the White House is tapping for the event are said to be "using their music to inspire audiences." It'll be a mix of established and emerging performers, but again there aren't any details on who exactly will be playing.
For film, the event will feature the 3rd annual White House Student Film Festival. The theme of the film festival this year was "The world I want to live in," and more than 700 short films from K-12 students submitted entries this year. The South by South Lawn event will feature the official selections for the annual film festival and also include some of the filmmakers themselves.
Attendance at the event will naturally be limited -- if you want to go, you'll have to nominate yourself here (or hope someone else nominates you). It's not clear what criteria the White House will use to select attendees, but it's still worth a shot throwing your hat in the ring if you want to hang out at the White House for a day. Nominations will be accepted up until September 10th at 5PM, so don't sit on this if you want a chance to go.