This page links to data from US states and territories Tide Stations to provide data regarding tides in that port. These links go to that stations homepage in turn and additional information can be viewed. Tidal predictions for over 3,000 sites.
http://tidesandcurrents.noaa.gov/tide_pred.html
Explores the challenges of tidal prediction and discusses tidal prediction in different water levels and with different instruments. Part of a complete lesson (Note a graphic is off on this page)
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter17/chapter17_05.htm
An explanation of how tides were measured manually in the past. Explores limitations of the system.
http://oceanservice.noaa.gov/education/tutorial_tides/tides10_oldmeasure.html