She is portrayed by actress Phoebe Strole.
Penny is first seen injecting a sausage, as Sam watches from afar. As he tries to leave, he knocks objects over, which makes Penny notice him. They have a quick discussion, and Penny gets ready to give Sam his shot. She tells him that she's not a real nurse, but only a sophomore in college. As Sam gets ready, he backs out. He hastily leaves the office, with Penny shouting out her name. He quickly ducks back in, and tells his. The two smile for a while, before Sam leaves.
Penny carries a box of needles, but a student knocks against her and she drops them all over the floor. As Sam sings Something, he follows Penny around the school. She is seen teaching a lesson on choking, and picks Sam for the demonstration. There is also seen to be a long line of male students, eagerly waiting to get inside the office. Later on, Sam enters the office to find Penny packing up. She informs him that Sue has fired her, as she accidentally switched a urine test and a vacination. Sam makes Penny give him the shot, and Sue doesn't fire her.
At prom, Penny is seen standing by the punch, and Sam walks over to her. She tells Sam that she isn't fired, thanks to him. After a quick chat, Sam asks Penny to dance, which she accepts. Penny is seen applauding Tina and Brett as they win Prom Queen and King.
Penny walks down the hall, and spots Sam, and makes her way over to him. She is seen with a tattoo, which she says is temporary and she wore it for a Skrillex concert. Penny talks about her "musical dark side", and he opens his locker. She spots a poster for True Jackson VP, and Sam explains the poster and show to her. Later on, Sam enters Penny's office, and he invites her to his Gaga performance, to which she accepts. Penny watches the peformance of Applause.
Sam goes to visit her after the performance, and Penny says that she didn't like it, as she isn't a fan of Lady Gaga. Penny admits that ever since preschool she has felt like she is plain, so she has dated bad boys. Penny lists her favorite musical artists, which includes Katy Perry. Sam admits he loves Katy too, and Penny mentions that Katy is going on a tour next year, and suggests they attend it together. He then says why should they wait a whole year and the two kiss, but Sam backs off. However, Penny kisses him again. Penny watches the performance of Wide Awake with Sam, and seems to enjoy it. They are also seen getting cosy with each other during the number.
Penny is briefly mentioned by Blaine, when he finds out Sam and Tina making out. He asks Sam if he just forgot about her.
While talking with Sam, Mercedes mentions Penny along with all of Sam's other girlfriends. Mercedes also thinks that she is over 30 years old.
- Main article: Penny-Sam Relationship (Pam)
In Tina in the Sky with Diamonds Sam meets Penny while she's doing an internship as the school's nurse Sam goes to the nursery to get a shot, but he gets scared and leaves, but knocks objects over and Penny notices him so Sam decided to get the shot, but he gets scared again and he leaves while Penny is shouting out her name and Sam returns to say his. Later Sam finds out that Sue fired Penny because she has no experience as a nurse, so Sam decided to get the shot and Sue will keep her as the nurse. At prom, Penny tells Sam that Sue isn't firing her. Sam asks Penny to the dance.