As it turned out, none of the other students who would be testing came to the next couple of classes, and I really wanted to work with them before we held the test. On the promised day, my youngest student came to class stating that she would be getting her yellow belt. I explained that it wouldn't be today, but that we would wait a few more classes until everybody had a chance to practice. She gave me a look and a tone of voice that left no mistake that I had broken a sacred covenant. She was more than disappointed and I paid for it the entire class period. While she typically has pretty good attention for a five year old and attempts everything asked of her, her demeanor changed this class. She let me know that I had let her down, that I had broken my promise, that she had come in ready to fulfill a high expectation and I shot her down. She didn't put in quite the same effort during that class, and gave me a look that left no doubt that I was being punished for my insincerity. Lesson learned: live up to your word and don't let some students down because others don't make it to class. Thank you, SG!
post script: we held the junior belt test tonight, and SG looked like a ninja! She has learned the sequence of moves expected of her in all three training elements (kata, kihon and kumite) and did them with confidence in front of instructors she doesn't really know. That Junior Yellow Belt is going to look good on her. I hoped I've gained back a bit of her trust in the process.