Remote phone access

[#1]

My teenager is going away to a tech-free camp (no cell phones, laptops, tablets, etc) for a few weeks.  There are phones available but the campers need to have phone cards to make calls.  Is there an access number and pin that I could provide to my child to have calls billed to my FIOS Phone account rather than having to go purchase a prepaid phone card at a retailer?  I may sound like a dinosaur but recall my parents having this feature through their long-distance carrier in the 80's and 90's.

[#2]

Wow that is a long time ago. And I am well into my 60’s

those calling cards by AT&T and MCI and Bell Telephone I believe are long gone in the past. Today even the ability to dial in to a toll free access number and enter your home phone number to make calls are gone. (Not a calling card but access number) 

you may have to get the prepaid card for your child.