"Higher Education": after it turns out that the teacher had forced Joy into sex and gotten her pregnant, you realize the other girl, Patti, who was at the teacher's house, was probably next to be abused. Also Rewatch Bonus for the opening scene: now it's clear he was already flirting with Patti.
How many high schools are in this unnamed city? You'd think after a while, they'd have to solve another crime at a school they'd already attended, which would cause lots of trouble if anyone remembered them (even the faculty was usually kept in the dark about the operations). Or a student who went to one high school where they were undercover, transfers to another school where they're undercover, and recognizes them. What if a student has friends who go to another school? Can you see the gang ever coming across someone they had to socialize with on a previous assignment?
Similarly, how many schools in the city can end up with new students suddenly transferring in with the semester already in progress, who turn out to be cops? You'd think at some point teachers and school administrators would have some urban legends going around and be wise to the ploy.
This might be the reason for Penhall and Hanson's recurring cover as the MacQuaid brothers; given their reputation, no one would ever be surprised that they suddenly left, or suddenly showed up at a half-dozen high schools during the roughly four years that Depp was on the show.
This even goes both ways; in "Back to School", Judy and guest-actor Officer Rocky are swapping recommendations for especially good teachers, who are worth learning from even years after an officer has graduated high school.
So Penhall's wife and true love Marta gets extradited out of the U.S. and he does nothing to go look for her for half a year. Then, when he, due to a set of unforeseen circumstances, winds up in Florida unplanned, decides on a whim that he'll now go to El Salvador to look for her. Confusing and illogical on so many levels:
He says he'll go to El Salvador now because "I'll never be closer". But wherever in the U.S. Jump Street was located, a flight from there to El Salvador couldn't have been so much longer or more expensive than from Florida.
Not only did he not pack anything to travel; he couldn't even have had his passport with him (seeing that when he got into the bus that got him to Florida, he didn't know that that bus was going out of his state), so how did he get into El Salvador?
Fuller was already very pissed that they had wounded up in Florida, but apparently now two officers of the Jump Street team can suddenly take up vacation days (at least we must assume they did, they can't just have decided to bail from work) at the same time, without beforehand notice? Also, they should at the very least first handle the paper work regarding the suspect they had in the previous (Florida) episode (and they would have to do that in Jump Street) before leaving.
More like Fridge Horror, but when they reach Marta's village, she has died just a few days before. Which means that if Penhall hadn't waited all those months, he, even if he couldn't have prevented her death, at least could have seen her again. That takes the Tear Jerker level of her death up to eleven...
Then Doug takes the underage nefew, Clavo, of his deceased wife, out of El Salvador and to the U.S. to live with him (it is implied he adopted Clavo). How is this legally possible? They never went through an official adopting process, and he took Clavo with him to the U.S. on a whim. Even supposing Clavo has a passport (a stretch, for a minor in such an, at the time, civil-war-ridden, human rights violating and corrupt country) and thus could fly into the U.S. with Doug, Clavo still must be an illegal immigrant officially. On that note: also Fuller must know Clavo is an illegal immigrant; that would Fuller get into trouble as a police Captain.
In "Higher Education" a teenage girl who's gotten pregnant by her high school teacher tries to hide the fact that that teacher's the one who got her pregnant by claiming that it was Ioki who got her pregnant. Now, both she and the biological father of the baby are white/Caucasian, but Ioki is Asian—which has lead to viewers thinking this is a plot hole claiming "as soon as the (wholly white) baby would have been born, Ioki would have immediately been ruled out as the father since the baby wouldn't look in any way Asian". But... the girl claiming Ioki to be the one she had sex with is actually the smartest thing for her to do under the circumstances. First, to her he's just some boy that went to her school a few weeks ago but now is gone away and nobody knows where that boy is. Because nobody knows of this boy's whereabouts, she could conceal the identity of the real father while not getting another boy of her school in trouble. note — Also, DNA testing already existed then, so the lie would have come out when the baby was born. — Secondly, and pertaining to the "race" point: who besides the girl remembers Ioki ("Jimmy", to them) was Asian, especially by the time the baby will be born? He's been gone from the school for a while, and was there only very briefly to begin with. And considering Ioki's a cop and careful about evidence of his whereabouts (plus, this was pre cell-phone age), there wouldn't be any pictures of Ioki at the school/dance either.
Though intentional or not, Jenko's remark of "Fuck you, Glee" could be construed as a comeback to the 2010 Christmas episode of the series where Chang says to Santa Claus, "I wish Channing Tatum would stop being in stuff."
Extra funny because of the extent to which Dawson Casting is used in both Glee and this movie.
Why does Jenko begin to view the Schmidt family as his own? Well, Word of God states that his father is Captain Jenko of the original series... who died after just six episodes of the series. As he graduates high school in 2005 after being held back two years, Jenko would have only have been a few years old at the time of his father's death in 1987, so of course he would begin to view the Schmidts as his family, it's the probably the closest thing he's ever had to a real family.
During his actual Highschool years the only thing Jenko had was popularity. Now he returns to find that he doesn't even have that? Suddenly his anger at the change in the social norm becomes a lot more understandable doesn't it?