Doug's Shock Therapy / Doug Is Hamburger Boy - S3-E11
Plot hole: Doug recalls previous years (in a flashback, where he was next to Skeeter at the window of the Honker Burger as they looked outside) of seeing the Hamburger Boy when Mr. Dink is confessing that he *was* Hamburger Boy. However, Doug has only been living in Bluffington for one year - this was his first summer there.
The Red Sea Sharks: Part 1 - S3-E1
Plot hole: When Tintin is listening in on Dawson's conversation, he realises an alarm clock had been planted in his coat pocket as a prank by Abdullah. Even if he didn't see the clock in his pocket beforehand, there is no reason why he wouldn't have felt the added weight the clock would have had on the coat. (00:09:35)