The banapple is a fruit invented by Quinn Pensky. It is half apple and half banana. Its only appearance was in the episode Backpack. Quinn's banapple tree was located outside and behind the campus. Quinn's banapples were in trouble, however, because the banapple tree was being attacked by birds. Quinn then fended the birds off by creating a laser scarecrow. The banapples are dangerous, however. In the end of the episode, Quinn says that something went wrong when she combined the molecular structure. This caused the banapples to taste badly, as well as make their juice a powerful acid. She demonstrated this by squirting banapple juice on Stacy's bike seat. The juice almost completely melted the seat of Stacy's bike.
Quinn told Michael and Chase that her banapple tree was originally a banana tree until she altered its genetic structure. She then said that her two favorite fruits of all time are the banana and the apple. Michael and Chase laughed at Quinn for trying to create another fruit. Quinn then said when the banapples ripen, the fruit will be edible and excellent.
An unripe banapple is green, and it will slowly turn pink and then red while it ripens. A ripe banapple is basically a red banana; It has the color of an apple and the shape of a banana.
In three weeks of the ripening progress, Quinn recorded the banapple's features. She said that it has a reddish-orange color, a smooth texture, and a "banapply" smell.