These uses include the use of flint for arrowheads and fire making, pipestone, sweat lodge stones, teepee rings, healing stones, and pounding pemmican. The students could describe and classify the rock samples. Make a class list of all the words that can be used to describe the pebbles. Remind them to try to use all their senses in creating these descriptions. Small plastic hand lenses are useful for this activity.
Some pebbles look different when they are wet, so have a pan of water available for each group.
Also have a nail or a penny for scratch tests to determine the hardness of the pebble. Wrap a large pebble in a towel and hit it with a hammer to break it. Provide each group with one broken pebble to examine. Groups could also compare how different types of rocks break. Rocks can be polished in a rock tumbler.