The teachers taught, they did not skim. We learned and passed exams, which involved memorising formulae etc (I did 3 separate sciences).
Exactly as DS and DD are now, though their sciences are arranged slightly differently.
If we read a book in English, then step 1 was to read the book from cover to cover.
Ditto for DS and DD today.
When i went onto university afterwards no one said that we weren't familiar with the basics.
My children aren't at this stage yet. From my DB's school in the 1980s, he was the only pupil to go on to university. Many left at 16 with few if any qualifications. DB might have been familiar with the basics, but many of his peer group were essentially familiar with very little else.
By the time, I'd been learning a language for 3 years, I could speak it and write it and I was very familiar with the various types of verbs -re, -ir, -er. My homework would be to memorise some more vocab or read a passage in French and answer the questions in French. My teachers always marked my work and gave some brief feedback.
Exactly ass DS and DD are today. DS is doing 2 languages to GCSE, DD will do 2 languages for 2 years but s unlikely to choose a second as a GCSE option.
YUR 1980s education may have been good. Mine was too. Your DC's current education may not be quite as you would like it, whereas I am very happy with DD's and DS's, as it is certainly a VAST improvement on my DB's comprehensive education in the 1980s and is very close indeed to my DH's private school one (he was at a middling publcschool, mine was perhaps a bit different because it was one of those 'academic hot house' types)