2 Way Tasks
This is a standard communicative language teaching activity - aka - Information Gap. Some other CLT activities you may know are: surveys, interviews, role plays, discussions/free talking. I choose 2 way tasks as the top dog because it is "controlled" and thus allows more scaffolding and success by students. Two, it has repetition. Finally, it is a task and has built in motivation to complete and finish. Tasks are a great way to get students "communicating" and not just memorizing or parroting without meaning. The basic thrust is to communicate meaning to another person. A two way task (aka - pair work ) does this with head on directness....
Basically you give students A and B similar but varying incomplete information. It can be text, dialogue, picture or even video. Then they have to fulfill a task to complete their own information. For example give two pictures - one for Student A / the other for Student B. Student A through questions, must discover and record/draw what is on the other picture. Student B, the converse. That's "2 way tasks in a nutshell ! Even watching Mr. Bean can be a two way task. Just show the video with one or two students describing the action while the other has their back turned to the screen. See these two way 2 way tasks for ready to go, "in the box" examples.
See this discussion for more resources along this vein; Pair work, communication games etc.... This is a great way to get your classroom "speaking" and producing language!
A couple "caveats". One - don't over explain the task! For instance, with these pictures below, let the students discover the way to ask each other for the information. This could be done in many ways! Numbered boxes, prepositions etc... Let the students control how to complete the task - they will enjoy it more. People love a puzzle! Two. If you are going to explain - model it. Do a dry run with a good student in the front and the rest of the students asking. Do the dry run without pens - pencils down! Then when in pairs, they can record the information.