"Yes, it's true," Ryan Murphy told UsMagazine.com. "She is a fan of the show."
According to Murphy, who is friends with the actress, Paltrow will "be playing a substitute teacher who Matt Morrison's character (Will) falls for."
He added: "She will be doing three or four solos."
This shouldn't come as a surprise as her next film, "Country Strong," has Paltrow playing a washed-up country singer.
"Country Strong," starring Paltrow, Tim McGraw and Leighton Meester, will be in theaters in December.
– The Hollywood Reporter