Continuity mistake: When Spark drops the sausages they fall on the ground. A shot later they're inside her kennel.
A Single Piece Was Lost - S1-E10
Visible crew/equipment: When the Gruenaks attack the Scientist a puppeteer is visible to the right of one of the Gruenaks, just before it grabs the bird cage and throws it onto the Scientist's head. (00:28:18)
Continuity mistake: After Molly tries the experiment and takes off her safety googles, they reappear and disappear randomly when she hugs Ed.
Continuity mistake: When Will Parry visits his grandparents, the grandmother is sitting on the sofa next to Will's grandfather. The grandmother's position keeps changing from sitting right next to him to being further apart.