The Mothers - S3-E17
Plot hole: When the "refrigerator" falls on Tobias's mom, the boys are watching from a side view. It is later revealed that the fridge was just a cardboard cutout. The boys were watching from the side, so how did they not notice it?
Visible crew/equipment: When Kathryn tells John that staring at his phone won't make it ring, in the next shot facing John the boom mic can be seen in front of him, bobbing around at the top of the screen. (00:02:55)
Revealing mistake: The swords Jayden and Dekker use often bend when striking each other, revealing they are rubber blades and not metal.
Continuity mistake: Chris has a blue dye pack explode on him, covering the front of his clown costume and face. But then shortly after, the dye is gone from his face and clothes.