Are you concerned that some kids will be playing in the classroom while others are still working (which is likely to distract the slower kids?) or is your concern that the teacher is not involved enough in the learning process?
Either way, I'd ask for an appointment to speak with the teacher to learn more about how things work in the classroom. Be ready to share your specific concerns for your child and be ready to listen to what she says about why she's doing what she's doing.
Don't let your concerns drag on - address them now so you and the teacher can get off on the right foot in this new school year.