Continuity mistake: At the start in class there are two people behind Meg who both have green tops. When the camera shows the class from the front one of the green tops has changed colour. (00:02:05)
Continuity mistake: When Meg tells her family she's a lesbian, Lois has food on her spoon. As Meg starts yelling about her friends liking her, Lois is holding a fork with no food on it. (00:11:40)
Continuity mistake: As the trio are singing at the end, the position of the 3 changes between instant cuts. (00:20:05)
Continuity mistake: When Neil points out the poster for Meg, Meg has 2 books in her arms that become one. (00:04:20)
Chosen answer: It's a real song called "Elvira". Originally by Dallas Fraizer in '66, however, this version seems to be the Oak Ridge Boys cover version. However, the mega lesbians skip the verse and just sing the chorus after the opening line.
Bishop73