The second event that may have made him nervous is that NC schools put a huge emphasis on End-Of-Grade tests, and this will be the first year he has to take them. Last year, when they were getting ready for the tests, the teachers spent a lot of time warning them that third grade was far more difficult so they have to work really hard, and informing them that the world was going to end if they failed their EOG's.
My dd13's 3rd grade teacher did that with the ITBS at the start of 3rd (they took it twice: beginning and end of the year). Dd came home from school physically shaking after day one of the test, burst into tears in the car, and did quite well none the less, but not nearly as well as at the end of the year when I'd convinced her otherwise about the importance of the test. I told her that the school & teacher were being judged on the results of their students' tests and therefore were stressed about them and telling the kids how big of a deal they were and that, despite what they were telling her, she was not the one for whom the test mattered. She always does better if she doesn't think that it is the end of the world.
I like some combo of bringing reality to the situation as to whether these feared events would really be as unmanageable as he fears and offering reassurance that some of the things you know won't be occurring (i.e. - x kid isn't in your class) won't happen.
