Have one student come to the front of the classroom and sit with her back facing the blackboard. Write a word on the board. For example, you might write "Christmas." The other students have to use their words to get her to guess the word on the board. You could also write words on the board that the students cannot say. With "Christmas," you could write words and phrases such as Jesus' birthday, Santa Claus and reindeer.
Divide the classroom into teams. The first student in each team must whisper a word to the next student, and they must keep going until the word reaches the end of the line. The winner of the game is the team who pronounces the word correctly, and that still has the same original word by the time they get to the end of the line. You should use phrases or sentences, instead of words, for older or more advanced students.
Assign a certain number of target words at the beginning of every week. The number should depend upon the level and ability of your class. Have the students recite the words daily. In the middle of the week, have them hunt through magazines and newspapers to find at least three examples of each of the words. Whoever finishes in the shortest amount of time should say the words and present the pictures to the class.
Have one student come up to the front of the classroom. That student should write down a word and let you see it, but not show it to the other students in the classroom. The rest of the class is allowed to ask up to 20 questions, but all of them must be able to be answered with either "yes" or "no." Once a student has guessed the word, allow that individual to come to the front of the classroom.