The Lab Brat

“The Lab Brat” was the seventh episode of the first season of Daria.

Summary
At Lawndale High, during science class, Janet Barch presents a lesson on acquired behavior on a lab rat, interloped with shows of her hatred of men and descriptions of how she had been left by her husband. The teacher’s dislike of males is shown extended even to male students while, on the other hand, she praises Daria’s imaginative answer to a question. She concludes the lesson by assigning teams of students for a home project, consisting on training a rat through a maze. Daria is paired with Kevin and Brittany is paired with Upchuck.

That evening, at the Morgendorffer’s, Helen asks her daughters about their day and Daria’s upcoming project, commenting that associating with Kevin could help Daria socially and ignoring Daria’s comments on Helen's lack of sincerity. Kevin arrives shortly after and Daria distracts him from the project by turning on the Pigskin Channel, while she retires to the garage to work.

Meanwhile, Brittany has arrived to Upchuck’s house under a heavy disguise. She warns him not to get ideas about her presence, but is blackmailed by Charles (with a photograph of her and Oakland's QB in a compromising position) into doing his personal chores.

At the Morgendorffers, Kevin continues to watch football in the TV and is oblivious of Quinn's flirting and continuous serving. Quinn seems intent on her efforts to seduce Kevin, even refusing Brittany's entrance to the Morgendorffers. Kevin eventually goes to the garage (breaking part of the maze Daria had already built) where he and Daria are surprised by Brittany, who quickly deduces Kevin hadn't been working and thus must have been seduced by both Morgendorffer sisters.

At another day, as Daria and Jane are discussing past events at pizza king, they are interrupted by Kevin (intending on arranging another visit to work/watch TV), Brittany (who tells Daria to stop seducing Kevin) and Three Js (who are in awe of Kevin and try to pick Daria up).

Brittany, meanwhile, plans and kidnaps the mouse used by Daria, passing it on to her brother and intending on exchanging it for Kevin (who by now is believed to be dating both Morgendorffer sisters). The next day, at school, Daria is able to trick Brittany into returning the mouse for Kevin. However, its stay at Brittany's has left it traumatized and worthless for the project.

The day the presentation of the science project comes: Upchuck has built an elaborate maze and trained the mouse, but Barch's refusal to let him speak and Brittany's ignorance of the project (as she had been too busy slaving for Upchuck and spying on Kevin) cause both to fail. As to Daria, she makes an insightful presentation on the mouse's fear as negative reinforcement, playing on the teacher's neuroses, and earns a top grade - whether Kevin, who had been mute and striking poses during Daria's speech, barely receives a passing grade.

“The Lab Brat” and Fanfic
The Lane cats Zachary and Taylor get into the act in "The Maze Thing" by Richard Lobinske.