These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Fair for Its Day: None of the girls may have been shown playing sports, being into science, or any other traditionally male pursuits. Valeria is the only one who is not afraid of mice. But keep in mind this was Mexico in 1989-1990, a very conservative society. Just the fact that all the girls had talents and goals- and they were heavily encouraged to pursue them- makes it stand out. Also, all minority students are usually treated respectfully- and when someone is mean to them (or to anyone else), they are quickly and politely told it is wrong.
Germans Love David Hasselhoff - Really popular in Brazil. So much it even got a remake, which is currently airing in SBT, the same channel that broadcasted the original version.
Girls Need Role Models: On one hand, most of the girl students had career goals. And they were wide- doctor, painter, writer, teacher, lawyer, fashion designer, etc. Marcelina is the only one who wants to be a wife and mother. On the other hand, most of the students' mothers were housewives. Most of the mothers shown working are those of the poorer students. The show's physician is male- and the father of one of the students. Most prominent working adult females are teachers and in other traditionally female professions, such as seamstress.
Purity Sue: Ximena, of course. However, she is a slightly unusual case in that she has no romantic interests or plotlines (unless you count the students who have crushes on her).
Pride: Maria Joaquina, who was egotistical and arrogant, often not caring about others.
When Maria Joaquina defrosted, she was replaced by Jorge; he was so prideful that he actually was enrolled in a public school by his dad to knock him down from his pedestal. It didn't work until the end.
Gluttony: Laura devoured food, romance novels, soap operas, celebrity gossip, and so on. Jaime was also noted for his huge appetite, though he wasn't as bad as Laura.
Greed: Margarita was extremely fashionable and dreamt of a boy giving her jewelry. Were she and adult, people would have easily taken her to be a Gold Digger.
Lust: Kokimoto often spied on the girls.
Wrath: Mario had a lot of angst at the beginning, and then his fear led him to hate almost everyone. Justified, given how his stepmother treated him.
Sloth: Jaime was very much a slacker. Adrian is shown being a sleepyhead.
Strawman Has a Point: Jorge tells on Bibi when she is trying to cheat on a test. Viewers are supposed to empathize with Bibi, since Jorge is such a despicable character otherwise. But Jorge has a point- it is wrong to cheat, and it would have been unfair to other kids who studied and took the test honestly.
Actually this was a Call Back to a similar situation in the beginning, where Maria Joaquina did the same to Marcelina and tried to defend herself by saying that she was taught to never tell lies or support liars. Similarly, we were supposed to emphatize with Marcelina rather than Maria Joaquina; OTOH, the other kids refused to talk to her (even Cirilo!), which caused Maria a huge Heroic BSOD and marked the beginning of her defrostment.
Unintentionally Sympathetic: Maria Joaquina. Sure sure, Cirilo's parents donating blood saved her mother's life... but all that means is that she needs to be polite and respectful to Cirilo- in no way is she expected to return his love. Maria Joaquina even had a fan club at this troper's school.
Conversely, actress Ludwika Paleta said in interviews that she was bullied by other children and got hate mail due to playing Maria Joaquina.
Unintentionally Unsympathetic: Cirilo. His unrequited love for Maria Joaquina borders on obsession- though he never stalks her. She is out of his league in every way. And yet he still refused to accept that she didn't like him in that way, making him the Dogged Nice Guy to end all Dogged Nice Guys. Had Cirilo being a few years older, he would've been seen as really creepy.
Values Dissonance: David sacrifices his pet turtle in order to make turtle soup for Fermin to recover from his illness. There is NO WAY this could have flown in the United States.
To a lesser extent, the Friend to All Living Things in this show (Mario) is male. In North America and Northern Europe, this type of character is usually female. And while most of the females have no issues in animals...all but one (Valeria) are murophobic.
Too Dumb to Live: Cirilo sometimes veered into this. i.e, when Valeria needed lots of fabric to make doll clothes and sell them to get money since her father's about to lose his job, Cirilo went and... cut off a sleeve from his mother's wedding dress. Naturally, Mrs. Rivera wasn't happy.
Ximena has good intentions, but sometimes reached this while trying to deal with her pupils. Namely, via lying to Valeria that she doesn't like her anymore as punishment for her class-disrupting antics — Valeria got so stressed and depressed that she fell sick.
The Woobie: Cirilo, Mario, and maybe Marcelina to a certain extent.