Student or Learner
I heard, " I canít believe she just called me on my crap like that."
I think the crap here refers to his lie or trick. Does "call someone on something bad he has done" mean that you've caught it?
Thanks a lot for your time.
To call somebody on something means to challenge them to justify something they have said or done.
'She called me on my crap' means that she picked up on something stupid I'd said and demanded that I explain it.
EDIT - Just seen Tullia's answer. That's good, too.
Not a teacher.
Yes, it means you are challenging someone on something they said or did.
In the card game of poker, only you know what cards you are holding. To call someone on their bet is to force them to reveal their cards. If they were lying ("bluffing") and you call them you reveal their lie. (And win the money.)