Revealing mistake: When all the kids are in the diner just before Chunk knocks over the water jug, Mikey starts to bang on the ground with a bar. When Brand stops him, Mikey calls him by his real name Josh. This is verified on the DVD by Sean Astin himself, in the commentary. (00:40:40)
Revealing mistake: When Charley stabs Dandridge in the hand with his pencil, he stabs the hand holding him by the neck. The depth of the wound on Dandridge's hand reveals that the pencil should have stabbed Charlie in his neck and given him a severe wound, if not kill him.
Revealing mistake: When the cook's body is lowered to the kitchen floor, you can see her move her outstretched arm closer to her head.
Revealing mistake: 1955 skateboard chase scene around town square. Note in this scene a metal device has been added between the kicktail and the back truck of the skateboard to create the sparks, then disappears and reappears throughout the whole chase scene. (01:03:40)
Revealing mistake: When the pancakes are sticking to the ceiling, you can see that when one hits the ceiling, it jumps. The pancakes were actually being dropped on the floor with an upside down shot. (00:05:45)
Revealing mistake: When Gary and Wyatt come home and see Chet turned into a pile of poo, Chet shoots his tongue from his mouth and catches a fly. Look closely, the tongue flies completely out of his mouth and is attached to a metal spring. (01:24:55)
Revealing mistake: During the scene when Audrey is having a nightmare about eating too much while on vacation, the nightmare ends with her inflating like a balloon from all the food. Her blouse splits open and down the middle, where the buttons have broken, the dark balloon used for the effect is visible. (00:16:35)
Revealing mistake: When Lowry first arrives at Buttle's flat to return the cheque, he hears a cough and turns to see a man smoking a cigarette, half hidden by a column. When he blows a cloud of smoke it is easy to see that it comes from a tube next to his mouth. He isn't even exhaling at the time.
Revealing mistake: When Stiles enters the locker room, a guy walks out the shower and you can see his black underwear. (00:05:25)
Revealing mistake: When Hightower throws the football to the hood, the hood flies back to hit the door. After he hits it, you can see the black wire that pulled him.
Revealing mistake: When Millbarge changes the missile's programming at the last instant, the rocket changes course simply by rotating the shooting frame - and even if it could change course like that, the angle of ascension would be wider than indicated on the bunker base's computer screen.
Revealing mistake: At the end, when the Colonel is at his control panel on the phone just after the nuke goes off, the cord from the phone begins to peel from the control panel. This is mentioned in the DVD commentary.
Revealing mistake: When Lane becomes depressed he goes out to the garage and ties a red cord around his neck and to the ceiling to hang himself. He thinks better of it, but his mother opens the door and knocks him off the steps and he hangs by the cord. If you look closely you can see that there is no cord hung around his neck, he merely holds his hand up and mimics grabbing the cord around his neck. The cord seems to be attached to something on his back. (00:15:40)
Revealing mistake: In the scene where Herbert and Dan re-animate the dead corpse, watch closely when Herbert rams the little buzz saw into the corpse's chest. At the bottom of the screen, you can see where the fake chest ends.
Revealing mistake: Remo, clinging to a tree trunk, is shot at by Grove using a vehicle mounted machine gun. Pieces of trees are seen shot but this is only sound and special effects. There are no muzzle flashes from the machine gun, the cocking handle does not move in time with the shooting, nor does the cartridge belt move through the weapon.
Revealing mistake: When Vernon is mad about the door to the library being closed and is trying to find a way to keep it open, at the bottom of the door there is a door stopper that would be able to keep the door open. (00:16:00 - 00:19:00)
Revealing mistake: When Jack and Joan escape in the F16, if you look at the back wheels, you can see the car driveshafts that drive the wheels. Jet aircraft don't have driveshafts.
Revealing mistake: When Tenderheart Bear confronts Nicholas in the Cave, the light of fire Nicholas has lit casts a shadow of Tenderheart Bear on the wall of the cave. However, when Tenderheart Bear moves his arms, the shadow stays the same.
Revealing mistake: When Kent rolls out of the front door with the popcorn, it is obviously a stunt double due to the man's hair being brown/black and Kent having blonde hair. (01:38:25)
Revealing mistake: When Mark is in the fitting room, it's obvious that his stunt double is playing one of the cuts in the 'mirror' as their moves do not match.