How many tides do we have in a 24 hour day? Do tides happen at the same time each day? Why? What is the difference between a high tide and a low tide? How do tides differ when we travel further away from the equator? Cool websites? these are the ones i found... http://www.sailingissues.com/navcourse7.html http://www.massbaytrading.com/TideClocks.htm