Plot hole: Near the end, Sam locks Mr. Howard and Ms. Briggs in a closet. Sam and Gibby then put a heavy desk right against the door and leave them stuck inside. Then later the two teachers are seen frantically controlling the students. How did they escape? They were inside a closet with the door locked on the outside and with a heavy desk against it.
Suggested correction: It's clear that another teacher or teachers heard the announcement or heard them yelling and let them out... What we should be asking is why no other teachers helped them control to the students.
IWanna Stay with Spencer - S1-E5
Revealing mistake: When Spencer turns on his iPod when talking to his Grandpa, you can see that the headphones are not plugged into the iPod.
Suggested correction: It is plugged in, but the cord runs from Spencer's head under his shirt and meets the iPod near where Spencer's green short sleeve shirt meets his long sleeve white sleeve shirt. Only a very short bit of the cord appears from under Spencer's sleeve to the iPod strapped to his arm.
ILike Jake - S1-E4
Continuity mistake: The locker that Sam has is introduced here, but in episode 3, she already has that locker.
Suggested correction: That's because the episodes were aired out of order, which isn't a mistake of the show. Episode 4, "ILike Jake", was the 2nd episode produced and episode 3, "IDream of Dance", was the 13th episode produced.