Here you will find 12 activities based on the TED talk by Kang Lee "Can You Really Tell if a Kid Is Lying?". Students practice listening and speaking most of all, but some reading and writing are required, too. They also work with their guessing ability and have fun trying to spot "the liar". There is a teacher´s planning, the student´s copy, the transcript of the talk and the answers to the questions in the exercises. As an extra activity I have included a link to a survey which deals with the fact of spotting fake smiles, and which all my students have loved.