There's really nothing that can fix either losing a phone or damaging a phone beyond repair.
Even if it is stolen while she's on the school trip and utilizes the built-in Apple 'find my phone' feature, usually the criminals are savvy enough now to wipe the device to disable that feature for quick resale. That's really your only option for that particular scenario- hoping you encounter a less tech-inclined criminal. The 'devices' <ahem> that alert you to setting a phone down (etc.) are either too cumbersome or way too 'rube goldberg' for me to really recommend for anyone in a practical real-world application. Teach her to keep phone in pocket at all times.
Otherwise, I would encourage you to put your foot down and tell her to leave it home and take along the dumb phone for emergencies.
My grand daughter is going to California in June with a high school group. She's 15 and she has lost one and the other iphone she ran over with a piano(don't ask). She had to save and replace both of these. I'm not sure how much responsibility that taught her. Anyway I'm looking for a security device that would alert her when she lays it down or can't find it and might also detect where it is. I'm not very savvy in this area and was hoping you all might have suggestions. If it were me I'd get her a Trac Phone instead to take but she of course can't live without her iphone 5. Any help would be very appreciated!

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