When it comes to revision, this is an activity I've found time-effective and motivating. After my students have worked on three texts in the textbook and done various comprehension and grammar exercises I use this activity to revise.
An essential skill in communicating and keeping up a conversation is the ability to ask questions. Students sometimes get lots of chances to answer questions but here is how you can get them to make some questions themselves!
This is a low preparation fun activity that works well with large classes, especially with young learners and teens. All your students need is a blank piece of paper and all the teacher needs is a little bit of imagination.