Today's classrooms are filled with many teaching assistants, volunteers, and specialists as well as the classroom teacher. At times, those assisting may not know how to help. There are some fairly clear do's and don'ts in this regard.
First, side talk is distracting. If the adults in the room are talking to one another, it's likely the students will lose focus. So as much as possible, don't side talk.
Sit with students. It's best to sit at a table group or along side students during the introductory portion of the lesson. This provides some special oversight and relationship building time with specific students.
Then when the work gets going, it's good to assess the room, and look for a student who seems to be lost or needing more attention if there is not already a targeted focus in place. Begin positively with that student by asking him or her to explain what he/she is doing, and then take an interest in their work. It's important to build good relationships during the year.
As you work with the students, keep your eyes on the class as well. If something is happening that shouldn't be, and it's expected, then provide a positive redirection.
It may often look like a teacher is casual in the classroom, but often that teacher is multi-tasking with targeted observation and help throughout the lesson. Students thrive when we model good learning and assist as often and as best as we can. Onward.