Prepare a handout prior to class that is a list of things not found in the Constitution. http://www.usconstitution.net/constnot.html
Pass out the list.
As a class activity, ask students what is and what is not, in the Constitution from this list.
Take a class vote (by show of hands) on each item on the list and post the yes or no vote (majority rules) on your blackboard, whiteboard, or overhead next to the item on the list.
THEN, hand out copies of the Constitution.
Move students into groups
Assign each group 5 or 6 items to find in the Constitution from your list.
Allow 20 - 30 minutes for search.
Have each group report their findings.
Some groups may think they have found reference to the list item(s) you assigned them. But actually, none of the items on the list can be found in the constitution. It's amazing what is not there.
Conclude activity by having each group come up with one or two things that they believe should have been included in the constitution that were not. Give them a few minutes. Then have each group share their ideas.
Prior to lesson 2, list all or some of the items the groups believed should have been included on the original constitution. Have that list ready as a handout prior to lesson 2.