Continuity mistake: When Flash plays tag with Faust ("Now you see me, now you don't"), there is a brief shot in which he rushes at Faust - but not inside Hyppolita's palace, but in some high-tech laboratory. Obviously a shot from some earlier series, since the coloring and style are different from the Justice League's.
The Catwalk - S2-E12
Continuity mistake: T'Pol says she has never been camping, but she went in "Strange New World."
Episode XXVII - Chicken Jack - S3-E1
Continuity mistake: Jack's father the emperor is a young man when he defeats Aku. At the conclusion of the movie, he greets his pregnant young wife. At the start of "The Beginning" movie, Jack is a very young boy, both his parents are well past middle age-and Jack has no sisters or brothers to explain the gap.
Continuity mistake: The back passenger tire blows and they come to a stop, You can see the tire is still inflated. But when they show a close up of the tire its burst at the tread. (00:21:20)
Crime of the New Century - S1-E9
Continuity mistake: In the fight scene at the start of the episode, Jesse knocks one of the GS agents into the water - in subsequent shots he has disappeared.
Continuity mistake: While Mr. Klimer is forcing Debbie into the car, he for some reason seems to have a Charlie Chaplin-esque moustache which he doesn't have in any other point in the episode.