The biggest Glee fans probably know everything about the show, from nerdy trivia to the most popular quotes. But like most Ryan Murphy vehicles, each episode is full of Easter eggs, meaning hidden jokes, references, and goofs that even the most hardcore gleek wouldn't notice. Don't believe us? Watch the video above to test your Glee knowledge.

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If you're looking for more goofs and references, this place is a good location to start. They list all the mistakes on the show, both intentional and unintentional ones. But probably the show's biggest "hidden" goofs are all the continuity mistakes that started piling up during the later seasons. All fans know that the show radically changed after the first half of Season 1. By Season 2, writers were scrambling to rewrite characters and create new plots to support an ever-popular show that was now selling albums and going on tours. According to Ryan, the changes were because the series wasn't actually meant for teenagers — at least not at first.

"I think the interesting thing about that show is that it started off as a 9 o’clock show," he said back in 2011. "To me, the inspiration and Brad’s inspiration and Ian’s inspiration was always Election, which had a really strong student and teacher story which was a satire about ambition. Our version was a little bit more heartfelt about teachers and the arts. But that’s how it started off. We never thought that it would become so popular with younger kids and it wasn’t designed for that. And it did. And then they moved it to 8 o'clock which was a risk. They said, 'Keep doing the 9 o'clock show and don’t change what’s working.'"

Although Glee underwent many changes during its six-season run, even getting a brand new cast in the later years, the fans couldn't help but keep tuning in for those musical numbers. "I feel that the second season was different from the first season in that it was bigger, bolder, more fantasy, more Top 40 hits," Ryan said in the same interview. "You write what you’re feeling when you're feeling it and I wanted the show to expand and it did. For all the criticisms, tribute episodes are the most popular episodes." 'Nuff said.