It depends. I've taught small group classes that had 0 behavior issues. The students just needed the extra academic support. I've had other small group classes where 1-2 kids were very disruptive both in and outside of the classroom. Usually they ended up in alternate placements by high school. Those classes were rough and not fair to the other students who were trying their best.
You can definitely email your DC's case manager and let them know your concerns or email the Special Education Department Chair. If there's more than one small group section of the class or a teamed class that's on the smaller side there's often a way to juggle schedules around if necessary.

Are the behavior issues in small group classes very common in FCPS middle school? DS is very distracted by other kids behavior yet I am concerned that he will fall behind in team taught setting. Please provide feedback on these two different options. Thanks