Paper lunch bags are numbered, and each bag contains one small,
strange item (a dinosaur key chain, an old-style fuse, guitar string
winder and other things they probably won't be able to identify by
touch).
They put their "non-drawing" hand into the bag and then draw the
object based on their sense of touch. When they finish drawing an
item, they return the bag to the table and get another. They spend
about 1/2 an hour with this exercise and it really does help them
"get" it.