(Not referring to the movie)
Adult/
GED Classes that are held in the evening for people who can't
attend during the day due to being a parent, working or high school (if you're 18 and attending both).
People who attend to Night School (or Adult School in general) are either getting their life together by catching up on their high school credits or who immigrated to this country to be successful, learn English, and get their
diploma (or
GED) in order to get a good job (or head to Community College/University if they choose to) so it's the best available option if you didn't finish high school and want to get your
Diploma or you can get your GED.