Continuity mistake: After Mortimer picks up Elaine and literally throws her out the front door, he locks it to make sure she doesn't just open the door and walk in again. When Aunt Abby goes to open the door for Mr. Gibbs less than a minute later, she doesn't have to unlock it.
Factual error: In the chemistry lesson on alcoholic fermentation there is written on the blackboard: H6P5O11 -> cane sugar, which is plain nonsense. (00:34:00)
Continuity mistake: When Bugs Bunny is shot by Elmer Fudd, he collapses to the ground and you can see there is a green bush beside him, but when we see Bugs in the next shot, the bush has disappeared.
Continuity mistake: At the flight station, when the captain addresses his men and says, "That's 28 men and 28 tries," the captain's ribbons, medals, and cap change colors. (00:03:15)
Continuity mistake: When Sammy Squirrel meets Screwy Squirrel, you can see that Sammy is holding a basket in her left hand, but in the next shot the basket has disappeared.
Continuity mistake: When Jerry goes to the door, you can see the telegram is by the letter box and after reading the telegram, he throws it away and jumps for joy. But when Jerry goes to show Tom the telegram, it is now back in its original position.