Once a week for 6 years of High School we had a "Personal and Social education" class, which was basically for school guidance, helping you get a job, apply for university etc. (90% of the time it was a "chill with your mates" class)
I think I remember watching a video in that class in 1st year about a guy who got random erections a few times (in class, in the pool etc) and it said that was normal? There mightve been a couple other videos that month too. I believe that's the extent of my sex ed.
I'm pretty sure biology touched on the reproductive process too, but more facts rather than guidance.