Continuity mistake: When Screwy squashes the truant officer's nose with a mallet, the nose jumps off in pain and then hides under the officer's face. At this point, the truant officer is wearing a hat on his head, but in the next shot the hat has disappeared.
Continuity mistake: When Screwy tells the wolf that he is in the wrong picture, he pulls down two titles card, the last of which has Screwy Squirrel on it. You can see that the title card has writing on the bottom of it, but when we see a close-up of Screwy in the next shot, the writing has disappeared.
Continuity mistake: When Screwy covers himself in white paint, he hits the truant officer on the head with a mallet. When he runs off, he has paint on him, but in the next shot the paint has disappeared completely.