Did he cheat or what?!

Ok, so you all know that Tucker's been going to Sylvan Learning Center working on his reading skills for the past couple of months. I also posted that he got an 85% on this years first spelling test when the most words he ever got right before was 2! Well, I got a note on Monday saying "congratulations, Tucker has passed his pretest with a score of 100% He can disregard all spelling pages in his homework packet and do only these 5 challenge words for the week!" I was so proud of him because I know he's been working really hard. It's not something that comes naturally to him. Yesterday, I was driving him to Sylvan and I mentioned that I wanted to come in and brag to the teachers about his 100% score. He informed me that he only got 100% on the test because he cheated! That really left me speechless!.....ok, almost! I told him how wrong this was and it's never ok to cheat. He told me that he had his homework word list on his desk during the test and his teacher knew about it. He seemed to think it was ok with her! Well, I just emailed the teacher regarding this. I made him do those disregarded spelling pages last night too! She informs me that Tucker DID NOT have anything on his desk during the test and even if he looked at his neighbors paper, that child is not good in spelling! She seems to think that Tucker made up the cheating story because the challenge words scare him. She assured me that he's been doing progressively well on his spelling assignments and he did a PERFECT job today in his phonics lessons. She's going to have a chat with him anyway! I am just dumbfounded! I don't know exactly what to think now....