Continuity mistake: At the start, when Data practices with the blue suction dart, in the close-up as the dart flies out we can see the mechanisms inside Data's invention. When it cuts to a tighter close-up, suddenly there is a spinning spool welded inside, which was not in the previous shot, that is retracting the orange string. (00:03:50)
Continuity mistake: In the opening scene where Data is using his sticky dart on his belt and being dragged towards the full bin, it changes to being empty just before being pulled in! (00:03:50)
Continuity mistake: When Andy begins to lose it in the tunnel, Brand holds one lit lantern at the head of the line and Mouth holds another lit lantern at the back of the line (Mikey holds an unlit lantern). Next shot the lit lanterns have switched, just as they reach Chester Copperpot and Andy screams. Then in the next wideshot before it pans to the skeleton, the lantern Brand holds up switches yet again. (00:53:15)
Continuity mistake: When Brand tells the others that the $50 bills are fake, Stef takes the newspaper with the Fratelli family mugshots off the post, from over the telephone. Then when Chunk gets the ice cream out of the freezer, the newspaper is back up on the post, but when the kids lift the dead body off the floor, the newspaper is missing from the post. Finally, in the shot just before Chunk shouts, "Guys, I'm stuck with the stiff," as the kids run into the fireplace, the tired newspaper is now lying on the printing press. (00:42:45 - 00:45:15)
Continuity mistake: When Sloth pulls the chains out of the wall, he picks up the Baby Ruth and there are no shackles around his wrists. He didn't break them, he only broke the chain at the wall.
Continuity mistake: When Mrs. Walsh shows Rosalita the house, the attic door is open and we see that it opens at the left, with the wallpapered wall behind it and nothing in front of it except the banister. When Brand opens that door and the boys rush up, we see the wallpapered wall behind it, only this time the attic door opens at the right. (00:11:25 - 00:13:50)
Continuity mistake: In the beginning scene of the cop calling out the inmates for their lunch, just as he calls "Hey Turkey." you can see the shadow of the supposedly hanged Jake Fratelli on the right wall. The shadow is totally inconsistent with the design of the cell and position Jake was hanging in. (00:00:45)
Continuity mistake: In the scene where the kids are crossing the wooden bridge near the waterfall, Data is seen holding a lantern. After he does his "slick shoes" routine, the lantern has disappeared.
Continuity mistake: In the scene where they are playing the bone-organ to escape, the Fratellis walk across the beam then climb the rocks to get to the room where the Goonies are. In one of the rocks there is a tall metal post sticking up. A shot shows one Fratelli brother stick his hand on this post to pull himself up, but in the next shot the hand is gone and a moment later the Fratellis emerge from the water.
Continuity mistake: When you first see Andy's hands being tied, you can see that they are tied fairly tight. Right before she goes off the plank, you'll see that the rope is barely around one wrist. In the next shot as she is going into the water, you can see her holding her elbows with both her hands. Then when Brand rescues her the rope is secure again. (01:32:40)
Continuity mistake: When the Fratellis leave the County Jail, the first police cruiser which makes the U-turn has a smooth chrome bumper with only a recessed license plate at the center, but when they make the first left turn, that squad car now has a chrome bumper with driving lights at each end and bumper guards on both sides of the license plate. It's funny how when they make the next right turn, the car style actually changes mid-turn, between shots - just before the second police cruiser joins the pursuit. (00:02:25)
Continuity mistake: When the back of the Fratelli's ORV is riddled with bullet holes, you can see they make a distinctive backwards "L" shape above the Jeep letters. Later, when Chunk examines the ORV, the bullets holes are now in different places than they were before, as well as two more holes in the license plate and the right brake light. Also, the license plate that is on the ORV when it is hit by the bullets, changes design as well. (00:02:45 - 00:30:30)