Matthew Morrison told some details to TV Guide about the episode's musical numbers:
"My assignment to the kids is to have them perform love songs, so we're doing some fun classics that are Valentines-y,"
Check out the set list.
Rachel (Lea Michele) - 'Firework' by Katy Perry
Puck (Mark Salling) - 'Fat Bottomed Girls' by Queen
Artie (Kevin McHale) - 'P.Y.T. (Pretty Young Thing)' by Michael Jackson
Tina (Jenna Ushkowitz) - 'My Funny Valentine' by Babes In Arms
Blaine (Darren Criss) and the Warblers - 'When I Get You Alone' by Robin Thicke
The Warblers - 'Silly Love Songs' by Paul McCartney
Right below you can watch the Glee version of Katy Perry's "Teenage Dream"
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