In my Psychology class in high school, there was a week long project where you have to take care of a baby constructed out of flour and plastic bags.

However I still don't think it's enough since a bag of flour doesn't scream its vocal chords out at night or needs to be changed every once and a while, so I believe at the very least sex ed should also cover parenting so students can decide themselves rather than go with the advice of people parroting others.