Learn how water pressure of the water turns the turbine, and the turbine turns a generator making electricity.
http://www.energyquest.ca.gov/projects/hydro-power.html
Water can be used to do work. Build a couple of water projects.
http://www.energyquest.ca.gov/projects/waterenergy.html
If you decide to build your own steam boat: You may build a working model of a steam boat using a thin and soft sheet of copper or brass.
http://www.freesciencefairproject.com/projects/steam_boat.html