Continuity mistake: The Nazi doctor shoves a coin towards the edge of his desk, telling young Erik to move it or he'd shoot his mother. In a shot from behind the desk, the coin is much closer to the edge than in other shots. (00:07:15)
Continuity mistake: After his mother is shot, Erik squashes the bell on the doctor's desk. Its shape is completely different in all subsequent shots. (00:07:50)
Continuity mistake: A sleepy Raven snuggles up to Charles and tells him to read something to her. He reads her his thesis. The way he holds his thesis and the way his left hand rests on the sofa behind her is different between shots. (00:13:40)
Continuity mistake: During the bar scene when the bartender is pouring beer for Eric, more than half of the glass is filled with foam (though it's in the background you can see it). But straightaway into the next shot when the bartender passes the beer to Eric, there is only a little amount of foam. (00:22:55)
Continuity mistake: Erik meets two Germans at the bar in Argentina, a pig farmer and a tailor. The amount of beer in the farmer's glass increases after Erik walks towards him. (00:23:20)
Continuity mistake: The bartender points a gun at Erik, and his finger is inside the trigger guard. When Erik pushes the trigger using his superpower, suddenly the trigger guard is free of the finger. This is intentional, intended to illustrate the fact the Erik pushes the trigger, rather than the bartender pulling it. (00:24:40)
Continuity mistake: Before Shaw takes the grenade from Hendry, the latter one has his finger in the pin, and has it half pulled out by then. Look closely at Hendry's hand: he is still holding the pin, while Shaw takes the rest of the grenade, but in the next shot, Shaw pulls it out again. (00:28:10)
Continuity mistake: When Xavier freezes Levene in the hallway he has a jet of water against his lips. In the next shot the jet of water is against his nose even though he didn't move. (00:30:45)
Continuity mistake: When the young mutants are showing each other what they can do, they all have a glass of cola, all four sitting on a corner of the table. But when Banshee wants to show what he can do, the glasses are instantly lined up. (00:51:00)
Continuity mistake: When Banshee is diving into the water, his "wings" are still attached. The shot angle changes, and his wings have disappeared before hitting the water. (01:39:20)
Continuity mistake: When Mystique is on the exercise table and Erik lifts the bar off her, her right leg changes from stretched out to bent from the different camera shots.
Continuity mistake: The position of the pig farmer's hand moves after Erik stabs it to the table towards the end of the scene.
Continuity mistake: In the original X-Men film, Xavier mentions that he met Magneto when he was 17. In this film, he doesn't meet him until well into his 20's.
Continuity mistake: In a scene where Xavier is pointing a gun at Magneto the distance between the gun and Magneto's head changes between shots.
Continuity mistake: In this movie, Emma Frost is seen as an adult woman [roughly around the same age as Professor X and Magneto]. But the character is also in X-Men Origins: Wolverine, set years later when Professor X and Magneto are much older, but in that movie she's younger than she is in this one. Although in Origins she is Kayla Silverfox's sister and her surname is never heard - the character was advertised and created as Emma Frost.
Continuity mistake: Towards the end, when Moira is pushing Xavier's wheelchair in front of the X-Mansion, when they stop, Xavier's wheel's position change between shots without them moving.
Continuity mistake: When Magneto is in Argentina, the two guys sitting at the bar change the distance between each other, between shots.
Continuity mistake: In the original X-Men movie, Professor X wonders why he can't read Magneto's thoughts, only to learn that Magneto has his special helmet. First Class contradicts this by establishing that Xavier knew about the helmet in 1962.
Continuity mistake: When Erik is about to lift the submarine out of the ocean, most of the hand he is using isn't that clean. However, after lifting the submarine out of the ocean part way and the shot cuts back to Eric, most of his hand is clean.
Continuity mistake: When Erik is first attempting to lift the submarine, he'd using his left hand. In subsequent scenes, specifically when Riptide turns into heavy wind to break Erik's grasp, he's now using his right hand.
Chosen answer: He's not okay with it, but he knows that Erik's views appeal strongly to her. To all intents and purposes, she's already made her decision - to try to stop her would likely only lead to an argument, which is not how he'd want them to part. Plus there is the somewhat major side issue that Charles has just been shot, so it's not really the right time for a discussion on conflicting mutant philosophies.
Tailkinker ★