Haley's 21st Birthday - S6-E10
Plot hole: The family mistakenly believes Hayley will be having her first drink. However, there were several instances in earlier episodes where they saw her drinking or drunk, or she admitted she'd been drinking. For example, in the episode "Arrested", the family drove down to bail her out of jail for underage drinking, and they saw the video footage, and the family members who didn't go were informed of the situation.
94 Meetings - S2-E21
Plot hole: April tells Ron that she's always known that he's Duke Silver because her mom has all his albums. So why didn't her mom freak out when Duke Silver appeared on her doorstep or, if she somehow didn't realize that Ron is Duke, even mention the resemblance? (00:20:35)
Plot hole: Dillon was quickly identified by the city sensors as having metal parts, thus classifying him as a threat to the city. Yet Tenaya, who is essentially a cyborg, tries out for the Green Ranger without setting off the same sensors.
Suggested correction: Tenaya wasn't caught because the guards assumed the equipment was faulty. It was giving positives all day because of all the sleeper agents we find out about later.
Plot hole: Cleveland never tells his friends where Cecilia lives. Yet Lester is somehow able to call Immigration & Customs Enforcement and direct them to Cecilia's house. (00:14:05 - 00:15:10)