Slope is a mathematical term for expressing change in vertical position with change in horizontal position. Architects and builders use the term pitch to describe the slope of a roof. Ship captains, road builders, and truckers use the term grade to describe the slope of a river or road. Ask the students if they ve ever seen a road sign showing a truck going down a steep hill. Gradient is also a term used to describe the rate at which a road, railroad track, or a river channel rises or falls.
All rivers have a gradual slope and eventually flow into a larger body of water such as an ocean.
Discuss with students different examples of where they encounter slope daily. Graduations are a series of marks for measuring that are equal in distance or value. This will allow the student to compare the amount of increase or decrease in elevation to the distance in miles between cities. The purpose of this activity is to identify where along the Mississippi River the gradient or slope is the steepest and the most shallow. The parts of the river that are the straightest are usually the steepest and the shallow parts are very meandering.