Last day at bike shop

My last day at Eaton Bikes is almost finished. A girl came in with a flat front tire, and through the course of a short conversation while I was fixing it, I learned that she might kinda want to know how to fix it herself. Great! I let the air out of the fixed tire, pull it apart and we go through the repair again. She does it herself this time, while I instruct. I don't charge for labor since she did the repair herself. Plus I just don't wanna charge six bucks labor for someone who wants to learn something.