The Oscar winner played a substitute Spanish teacher in the episode and chose to make the language she speaks fluently in real life a little more interesting by inviting her student characters to talk about modern celebrities.
In Spanish, she said, "Lindsay Lohan is totally crazy, right? Repeat... Repeat after me with more energy. Come on!"
Her character, Holly Holliday, then asked, "How many times has Lindsay Lohan been to rehab? Five times. Five."
Lohan is currently receiving treatment at the Betty Ford Clinic after failing two mandatory drug tests.
As well as showing off her comedy skills, Paltrow also sang and danced during her Glee guest spot - performing a mash-up of Singin' in the Rain and Rihanna's Umbrella with the cast and a solo rendition of Cee-Lo Green's Forget You.