When Brad was training to be a firefighter, he had qualified as an EMT (one of those people who stands at the sidelines and gives medical attention to people after they've benn rescued by the fully qualified firefighters) when Bernice's boyfriend, Zane, was trapped in a fire. Brad rushed into the burning building and saved Zane's life. But because Brad wasn't a fully qualified firefighter, all he got as reward was an official reprimand for breaking the rules. When his family and friends learn of this, they stage their own improvised mini-parade in Brad's honor.
Tiffany's Pet the Dog moment in 2009. Delta has been looking forward to the class trip to DC for three years. Unfortunately, one student had to be randomly cut from the trip and by luck of the draw, it was Delta. Luann and Bernice then organize an event to get Tiffany to be dunked at a game of skill to raise money; but Tiffany bails out because the water's too cold. A couple days later, she then walks by with Elwood after saying she felt bad for bailing on them and asked Elwood, who had volunteered to pay for it himself. This is easily one of the most heartwarming moments of the series.
Delta saying what she got for Christmas - sprouts, in a conclusion to her Hodgkins Lymphoma storyline.