A couple of things:
A Sim lives around 90 sim days total so your estimate of two years per Sim day would make them 180 years old.
Let us instead try with one year per Sim day. That makes them 90 a very reasonable life span.
So 12 days for child and teen plus 24 for YA makes 48. I would call that middle aged wouldn't you?
Then you mention your teens going to school in clothes you don't approve of. You do know that you can change their clothes right? And if you had teens in real life you would likely have had them change the clothes they wanted to go to school in on more than one occasion.
Kids tell jokes that make little sense but you laugh anyway don't you?
Lastly do remember that this is a game that are not meant to depict real life.
Edit:
I forgot your claim that a YA couldn't have a teenager. So lets examine that.
Lets just say that the YA gets pregnant almost immediately and gives birth at 27 (24+3) 13 years later she is 40 and has a young teenager. That sounds about right to me. What about you can you see a 40 year old being the mother of a young teenager?
