Younger students can measure the distances. This will help them understand yards.
Older students can analyze how an angle affected distance.
Discuss 1 9th century distances of yards traveled by a projectile to the miles of today's weapons. During the Civil War, the cannon's role varied from battle to battle. At Vicksburg, the Union had field and siege cannon from the Army and Navy. The Confederates had easy to move field artillery and the larger heavier guns at the river batteries. The gunnery crews became experts in mathematic sighting angles, target ranges, trajectory paths, charges and shell weight ratios were quickly calculated in the field under fire.