I walked out to my car and found the keys in the ignition
Why were your keys in your car?
I'm curious about that, maybe some kids did prank me.
I'm sure you are curious about your keys and it is natural to forget where you left things sometimes. Maybe you just left them there and forgot about it because you were in a hurry. It would be best to ask the kids in case they were playing a joke on you.
I get why you implied that I was forgetful. I am human, so maybe children did prank me. Whatever, funny as hell.
Well the only way to get to the bottom of it is to ask the kids. If you did leave them in there, try harder in the future to not forget them.