This is an interesting idea for a lesson which helps with checking reading comprehension. It also introduces some good listening practice.
After you have worked on a text with your class you will want to make sure they understand it. Quite simply you can read it back to them but making plenty of mistakes as you do so.
As you do this, your class listens carefully and when they hear a mistake they just shout out. The video on this page demonstrates how this is done.
It’s good for letting a bit of steam off with the class and if you can make the mistakes as humorous as possible then all the better!
NB try to make the mistakes factual rather than grammatical; you don’t want your students hearing bad English too much!
Reading Comprehension – reading comprehension with your TEFL class