This will be a simpler and cleaner way of doing the shoeprint activity suggested in the 2nd den meeting outline for the Paws for Action adventure (Requirement 2b(i). It would also be similar to what police would encounter when processing an outside crime scene.
What you need:
A folded towel, and 1 piece of aluminum foil for each boy.
Have each boy step on a piece of the foil. They don't need to stand still or do anything special, just walk across it.
Voila! A perfect, detailed imprint of the shoe.
Now you can play the game suggested in the den meeting outline. Lay out the pieces of foil on a table and have each boy find his own shoeprint. For another challenge, have them find a friend's shoeprint.