This one is from the Insect Guessing Game I have used, but I also have a Vehicle Guessing Game.
I find clipart pictures of the objects I want the kids to guess, and then I print them out as big as I can on a piece of 8 ½ x 11 paper. I glue/tape the picture to a piece of black construction paper and then write a little poem about the object and glue/tape it to the other side of the piece of black construction paper. I keep the picture face down, read the poem and let the kids shout out what they think the poem is describing. Below is a picture of the Grasshopper card and the poem I use to give the kids clues as to what insect I am describing.
I am big and green and I hop around
When my wings and legs rub together I make a lovely sound
You may see me on a field where you play soccer
Please don't squish me cause I am a … "grasshopper"
You can pick any subject and any objects in that subject; in my Vehicle Guessing Game set I have a school bus, airplane, train, car and boat. The kids really seem to like the activity and enjoy making guesses. I make sure that the objects are familiar and the poems are descriptive so that they are easily able to guess what each object is. Plus it is fun for me to come up with the little rhymes for each object.