23. Environmental Science (Season 1, Episode 10)
For me, this episode is where the study group really become the study group. It also includes a wonderful musical number of Troy and Abed really sealing their friendship as they coax a mouse back to its cage by singing Linda Ronstadts Somewhere Out There. Jeff is on glowing form here, not just as the cocky opportunist screwing everyone else over to help himself and emotionally manipulating a vulnerable Chang- we start to see his true colours here- but as the sweet guy who can talk big an has the groups best interests at heart. This is a real transition episode where the show quits running and starts to spread its wings and fly.
22. Introduction to Statistics (Season 1, Episode 7)
This Halloween special is in here not so much for Jeffs attempts to get with Michelle Slater (who was never one of my favourite characters, though she had her moments), but for what happen at Annies Dia de los Muertos party. Pierce tripping as The Beastmaster (from the movie Beastmaster) is the highlight of the episode, but Abed as Batman gets me every time. The first themed episode we are treated to, and still one of the best. Its also where Ludwig Göranssons score begins to stand out, so its up here for that, too!