A functioning high school is what I really would like, that we could follow kids to class or actively play as a teacher (both optional of course).
Even more than that I'd want the same thing Primary school for kids
And the feature I want most is homeschooling haha!
I'm in Canada and I had 3 high school years (10-12)and 2 middle school years (grade 8-9)(and 8 elementary school years (K-7).
HOnestly I'd love to see the teen life stage divided so we have preteens. Kids that can have a first crush/date but can't woohoo. Kids that can babysit, but only for younger siblings. Kids that get a paper route (that's still a thing where I live and everyone gets a free weekly newspaper here as well as the option to opt into paid ones). Kids that go to middle school, not high school etc.
I want subject homework and doing it raises skills in those subjects. Maybe even a tie in to uni scholarships (get an A in Math you can get a math based scholarship or something)
Field trips would be great!