Party Central

Party Central is a 2013 Pixar computer animated short directed by Kelsey Mann. It first premiered August 9, 2013 at the D23 Expo in Anaheim, California and was shown in theaters with Muppets Most Wanted. Party Central is the second short in the Monsters, Inc. franchise and takes place shortly after the events of Monsters University. The short involves Mike and Sulley helping their Oozma Kappa fraternity brothers make their party a success.

Once they have the party fully stocked, Scott Squishy Squibbles mother Sherri walks in on it while doing a load of laundry. She is angry with the fraternity, but only because they did not invite her. After lighting a bonfire on the lawn, Sherri introduces the crowd to door jamming, or jumping from the roof with the help of two doors to land safely on the lawn. The guests congratulate the Oozma Kappas for throwing a great party, and many of them decide to pledge the fraternity.In a postcredits scene, the husband and wife wake their son Timmy up and ask if they can sleep with him, saying that there are monsters in their closet. Their son vehemently replies, Thats what Ive been trying to tell you ........

Source: Wikipedia