'The Secret Life of the American Teenager' 100th Episode Airs Tonight!

The cast and crew of The Secret Life of the American Teenager snap a pic in front of a yummy-looking celebratory cake in this new still from the set.

“I Do and I Don’t” marks the 100th episode with Amy (Shailene Woodley) starting her first day of senior year. And a senior year means a flash mob with Ricky’s (Daren Kagasoff) on a stick!

Check out Renee Olstead and Camille Winbush singing “Marry You” for the flash mob below!

“When I signed on, I didn’t think about award shows, magazines, the amount of episodes, but to get this far and accomplish 100, it’s crazy to wrap your head around,” Shai told TVGuide.com. “The most exciting thing about it is that all of us have seen each other grow and have a lot of first experiences on the show. It’s really special to have those kinds of people in your life.”

“I Do and I Don’t” premieres TONIGHT, Monday, June 25th @ 8PM ET/PT on ABC Family.