The 17-year-old reality TV star was thrown a surprise graduation party by mum Kris Jenner, which was hosted by American Idol presenter Ryan Seacrest.
Sisters Kendall Jenner and Kim, Khloe and Kourtney Kardashian all attended the lavish celebrations, as did Kylie's rumoured rapper boyfriend Tyga and best friend and model Gigi Hadid.
Kim shared a snap taken in a makeshift photobooth on her Instagram page of her sisters pouting and licking a doughnut.
The 34-year-old pregnant star also shared a picture of herself with Keeping Up with the Kardashians producer Seacrest, and added the message: "Thanks for hosting Kendall & Kylie's graduation ceremony!"
Kendall's 2014 graduation was also being honoured at the party, although parent Caitlyn Jenner was not present.
Kylie shared an image of herself holding her diploma from Laurel Springs high school, which she attended until 2012 before being home schooled. She thanked Kris in the accompanying post, writing: "I love my mom for doing this. "Thank you for making this experience as normal as possible for me."
In further snapchats, Khloe displayed her twerking skills, while matriarch Kris seemed impressed by the synchronised swimmers' pool display.
Naomi Gordon is news writer mainly covering entertainment news with a focus on celebrity interviews and television.
