Here's what I think.
Is the kid happy? Yes. Cool.
Is the kid unhappy? Yes. Be sympathetic and talk about how you're going to make the best of it.
Still unhappy? Give them cuddles and chocolate biscuits.
Still unhappy? Take a deep breath - you're going to be having a lot of chats this year.
Stillll unhappy (five weeks into term)? Sure, speak to the principal. But just give it some time and give your child a chance to make a go of it.
Embrace vagueness and relief that you don't have to front up to school to deal with it all each day and it will leave you the energy you'll need for your empathy and chocolate biscuit buying.