Lunch Money

I had a parent call me about some missing money this morning. She told me she sent her son off with $100 cash to put toward lunch credit but the money never made it into his account. I called the young man to my office to find out the whereabouts of the money and he said he made an "exchange" with you for a service. What kind of service was that? I'm going to get to the bottom of this, young lady.