4. Mario Lopez
Dorothy's career as a substitute teacher is important to her even though she only spends brief periods of time with each class she visits, she wants to better her students' lives. When Mario (clever, huh?), a young Cuban boy she tutors, authors a moving essay about his family's life in America, Dorothy decides to submit it on his behalf to a contest, believing a win could open up new academic possibilities for him. Unfortunately, all the submission does is clue the INS into the fact that Mario and his family are in the U.S. illegally. Mario, of course, is a 13-year-old, bemulleted Mario Lopez, long before he would insult Zack Morris for being a preppy or cheat on the Doritos girl. His worried, angry performance is very well done as he rails at Dorothy for ruining his life. Dorothy, wracked with guilt, promises to fight for Mario and his family she even speaks on his behalf in court. In a rare instance of realism in sitcom world, though, it does no good Mario and his family are deported.