I'm a first year teacher. Last semester, I felt like I had good control of my classes. However, this semester, I'm teaching a grade 11 chemistry class, and I feel worried about my classroom management in that course. They are extremely chatty. It feels chaotic and loud to me, and I'm usually stressed out by the end of it. The class has 40 students. My classroom is a lab room, so the students aren't in desks, but are sitting at lab benches in groups of 5. I taught 40 students in the same room last semester, and it went fine. This time, there are large friend groups in the class, which is making it more difficult. Also, we're currently doing a review of grade 10 chemistry, and many of the students are bored because they remember the material. At first, I had to keep reminding the students not to talk at the same time as me. I made a new seating plan, and it worked really well for one day. Now, it keeps them from talking while I lecture, but when I give them work time, things still get really loud. Many times, they are off-task. Today, there were about 6-10 minutes left in class. Students at the back of the room were asking me questions, so while I was answering them, students at the front started packing up and getting out of their seats. That lead to most of the class packing up early, even though I reminded the students last week not to pack up early multiple times. Another teacher at my school told his students that if they pack up early, he will give them less time for their unit tests. I got frustrated with a group of students that was standing beside me, and I threatened to do that. Now, I regret doing so because I feel that it's an unfair solution. I'd appreciate any advice. Where should I go from here? What are your strategies for dealing with a really chatty class? I am feeling discouraged.