They can be good for beginners because they can see how they can use the few words they know. Intermediate students often hit a plateau and role plays can help them grasp more words for specific situations. Role plays can help advanced students become more fluent in English.
Children really enjoy doing role plays since they often pretend on their own. When left on their own children are likely to play house, pretend to be dinosaurs, or act in any number of situations. Using role plays with teens is a great way to get them up, doing something, and involved in the class. Adults might already have experience with role plays in the workforce, at training events for example.
Different Ways of Learning
People learn differently and some people learn by doing. If you combine speaking a foreign language with actions they may be more likely to remember.
Students are able to get immediate positive feedback through applause and verbal feedback. Both you the teacher and other students can tell the actors what they've done well.
Review the Lesson
Role plays allow students to use new words, expressions, and grammar in a suitable context. By using what they've learnt earlier in the lesson straightaway, they are more likely to retain what they've learnt.
You might want to check out fun ESL plays for children, role play ideas that work, and example role plays.
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