Continuity mistake: At the end in the hospital, Maggie's bow is red for a second, then it changes to blue.
Continuity mistake: All through out the episode, Bart draws his pictures with only one pencil, but they all end up in color when he's done.
Factual error: When the creator of Danger Dog draws a picture of Skinner on a notepad and puts it on the projector, it is perfectly visible. It shouldn't have been, seeing as the pad was so thick.
Continuity mistake: When Homer falls into the pool with green paint, most (but not all) of him is covered with paint. In the next close up shot, he's completely covered in paint.
