Thanks for your reply. I will try to demonstrate certain activities before getting them to start.
I'm in Indonesia and I'm an Indonesian as well as the students. 2 years ago I was working as an Art teaching assistant in an international school and once I observed one of the teachers teaching ESL to a group of Korean students. Yes they tended to chat in Korean but they were a bit more active in participating in activities.
Back to my current students, they probably had the other teacher for at least one month. Seeing the classroom atmosphere, I had to change one of the activities in the first session bcoz I was worried it might have been too hard for them.