Simple yet practical exercise.
I use it for my students through 7-8 year olds. Any plastic bag will do. Collect various objects- a coin, watch, ring, scissors, a battery, medicine, etc.... I simply say
"Whats in the bag?" The kids usually parrot this back to me. Take the objects out of the bag, One at a time, identifying each one. When the bag is empty, give the students the opportunity to identify each object. I pick a student and say " I want the (item)" You'll be surprised how enthusiatic the kids are about the game, and how willing the are to compete with each other in identifying the objects. After all the objects are identifyied, I say "Now, I'm going to put the (object) in the bag" and toss the object back into the bag.
A simple yet effective vocabulary builder. All practical words to know. And the "What's in the bag?" provides a basic grammar exerciese as well.