Give each person an index card and a pen. Instruct them to write down two truths and one lie about themselves on the card. (Not necessarily in that order!) I've found that by having the patients write down their three statements, they remember them better and it makes it harder to tell which one is the lie.
After everyone has written down their three statements, select one person to go first. This person reads his three statements and the group tries to guess which ones are true and which one is false. After the group guesses, have the person reveal whether or not the group was right. Then select another player to go, and continue doing so until everyone has had a chance to read their statements.
After everyone has finished, I like to lead a discussion about communication We talk about non-verbal communication, body language, tone of voice, eye contact, etc. and how that relates to how we communicate with one another. It also helps us get to know each other and feel more comfortable as a group.