Thanks everyone for your comments. As I identified at the start, this was more a vent than anything else.
I thought about it for a couple of days and I realized that my reaction wasn't really about being mad about someone else getting to be the lead instead of me. Like I said, the lady who is the lead is a cool co-worker; she's competent and friendly.
It's just that I have such a deep compassion for this group of students and I want to make sure they get taken care of. I guess I was more worried than anything else. I'm often rather task-oriented and that's how I sometimes approach getting things done. I realize now that it doesn't really matter how we get "there" as long as we get there.
Thanks again for listening.
.....Kelly