Here's my 90's kid ETX experience.

4th grade (I think) boys and girls were split and we were given a very basic overview of our bodies and how they work. It took 30 minutes to an 1 and a half at most.

In 6th grade we received a booklet that showed us a fairly detailed medical view of the male and female body, watched a video about pregnancy/"stds", and had a short q and a it was all covered in an afternoon.

The sex ed we had to take was in 9th or 10 grade and was a every other day 1:30 minute 12 week class. At my school the cheerleading / dance coach taught sex ed. She refused push the abstinence only bs the district wanted her to teach and argued with the school until they let her run her class how she wanted. She answered anything that was seriously asked, taught us about STIs in more detail, about pregnancy,birth control, went over common drug, how to use condoms, where and how to get supplies\help, etc. I went in expecting it to be useless but it was actually educational.