Well, this has been interesting reading. If this were me on the scene, I'd be calling a medic--I'm about 3 weeks away from finishing off my EMT-B course, but for purposes of this scenario, I'm assuming I pass. I've been running as an observer and driver for about 18 months. So there's my (in)experience caveat.
That said, a helo sounds excessive in this instance. At least in my area--we've got 3 hospitals within 15 mins. Actually, the only times I can think of a helo being suitable here (disclaimer about inexperience being noted) is if we had to send someone to a burn center or some other specialized facility (up to Hershey Med Center, down to Shock Trauma, whatever) where drive time would be putting the patient at undue risk.
If, in some unimaginable reality, the medic deigned to ask my input (other than "ya know where to hook these up?" for his leads), I'd tell him that the slamming heart rate doesn't look kosher (yeah, that's me: understatement of the obvious), and considering she's in high school, I'd be thinking she's on something. I mean, Hell... that's why they call it high school, ain't it?
Later!
--Coop