Revealing mistake: The ghosts often cast shadows.
Suggested correction: You can also hear their footsteps. But I'm not sure this is a mistake, just their own perception. Within the ghostly world they appear and act just like they would in life.
The ghosts are manifestations of energy, therefore they have no physical body to block light. Even if in the ghostly world, physics are physics and there should be no shadows.
Continuity mistake: When Eden confronts Kinsey by the lockers, as the angle changes so does Kinsey's arm. In some shots, she has her arms crossed and the locker door is closed, in some shots she has one arm up, holding the (open) locker door.
Continuity mistake: An employee is asked to leave the computer lab, he actually exits it twice. (00:11:15)
Who Burned Mr. Brinker's Store?: Part 1 - S1-E6
Other mistake: The arson investigators name Jamal as the main suspect in setting fire to the store, because the security camera caught him sliding something through the front door mail-slot. Any arson expert would immediately know that it wasn't Jamal that started the fire, as the fire's point of origin was in the back of store, and was also entirely contained there, and Jamal was not only nowhere near the back of the store, but was also outside.
Other mistake: You don't have to look further than the name; the title of the series is "Knight's and Magic" instead of "Knights and Magic".
Revealing mistake: During the opening theme, when the children are watching the magician, you can tell they were not actually filmed together. The magician scenes are filmed more professionally using a sharper tape or film image, whereas the children scenes look more like a standard fuzzier film-type such as on a projector (primarily used at that time).
Other mistake: Curtis grabs Alisha's hand without activating her power. (00:16:45)
Factual error: In the last minutes, the show looks forward to future challenges, in effect a preview of the never-made 3rd series. The oracle says they must find "the golden fleece, woven long ago by the Stygian witches." But the golden fleece, or indeed any fleece, is not a woven fabric. (Today's fleece is a modern invention).
Episode #1.2 - S1-E2
Other mistake: The very first word of the opening title contains an embarrassing typo, considering it's the name of the main character: It reads "Maud'Dib", instead of "Muad'Dib".
Continuity mistake: In the final showdown between the Queen and Alice, in the wide shot, you initially see the Ten of Clubs standing beside the Queen, but when it moves to close-up, he has disappeared from her side, only to run into the scene behind Jack and Duchess moments later. (02:52:45)
Continuity mistake: Ruth Deaver is helping Alan Pangborn put on his tie. The camera is facing Ruth's back and we see Alan's face in the mirror. The camera then switches angles to face Alan's back and Ruth's face. Alan's collar which was popped straight up from the first angle is now perfectly down over his newly tied tie from the second angle. (00:24:55)
Visible crew/equipment: When Miss Hawk is speaking to Edward by the well, the boom mic can be seen in the top right of the screen.
Other mistake: When Teela is at Snake Mountain, she overhears TrapJaw saying how Skeletor's electrical creature will control all of the machines at the palace. When Teela returns to He-Man, she says that the creature Skeletor created is called Byte. There's no way for Teela to know the name of the creature, since TrapJaw never referred to it by name. (00:14:24 - 00:15:20)
Take Me out to the Ballgame - S4-E3
Revealing mistake: When the fat guys are running down to stop the bad guys, you can see the blue safety mat that they land on just after jumping. (00:37:00)
Pride Parade - S5-E3
Factual error: Nandor manages to fly up to space, then loses control and falls back to earth in a fireball as he reenters the atmosphere. But objects reentering the atmosphere only get hot because they're generally travelling at immense speeds, 7-12 kilometers per second. Nandor just floated straight up, then falls straight back down. When Felix Baumgartner parachuted from the edge of space his maximum speed was about 1,300 km/h, and he didn't catch fire.
Witchcraft! - S1-E5
Visible crew/equipment: When Jonathan shuts the stable door the camera lights are reflected on it.
Continuity mistake: Multiple times throughout the show, Kimber can be seen in quick shots with light pink hair (the same color as Jem's), when her hair color is actually a dark pink/red color. (02:00:00)
Continuity mistake: When Marshall first finds Trip's letter, he holds it from the left side. In the close-up, he's holding it from the right side. (00:02:10)
Continuity mistake: Throughout the episode Lieutenant Abbie Mills' lapel mic changes from scene to scene. It goes from the Motorola Commander Speaker Mic to a standard Motorola mic without the orange emergency button, volume control, 16 channel selector knob and 2 programmable buttons.