Show and Tell
Each day four or five different students have show and tell.  In the morning they put their show and tells into a special sack so that what they brought remains a surprise.  During show and tell time each student comes up in front of the class and gives three clues as to what is in the bag. 
The show and teller then calls on other students to guess what they brought to show.  The trick is they may only ask "yes or no" questions. 
This show and tell was figured out - a dinosaur!

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