First, you need to make friends. When I taught kids, my purse was full of candies and stickers. ( Chinese kids are very shy ).
You can walk in the classroom and use the " chong-fu " for smaller groups of students.
What`s the age of these kids ?
If they are 6-8 years old, you can use short rhymes:
" Jellyfish, jellyfish dance in the sea !
Ouch ! A jellyfish sits on my knee..." (plus some body language )
Invite 4-6 students in front of the classroom and let them perform ! Don`t forget to ask applauses from the audience and to give each of them a sticker.
Then, invite 6 more kids and so on...
For older ones ( 8-12 ), you need longer roles:
For boys: " My name is Steven. I am a king. I am very strong. I can bang the gong...."
For girls: " My name is Ann. I am a queen. I have a ring. I can sing a long song..." ( Let them sing, if they want to !). Why not some paper crowns and plastic rings for the young artists ?
Create such roles by yourself ! ( with some "hidden grammar" sometimes )
Personally, I spent much time assisting Chinese kindergarten teachers at weekend. They are graduates of special colleges in China.
For the age 12-14, you can start some debates like :" What can you tell me about China ?"" Chinese inventions ", " Animals in the desert ", "Dolphins ", " Animals with long lives ", " Polar bears ", " Kites "...
I agree with Rheno 747. TESOL and TEFL courses are not very useful, especially in China, where teachers must handle classes of 50-80 students. I met an Australian teacher, who spent more than 2000USD on such a course and couldn`t teach properly. She was exhausted and full of chalk after each class.
( too much body language ).