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Website
NOAA

Noaa: National Data Buoy Center: What Are Tides?

For Students 9th - 10th
This site from the National Data Buoy Center presents a brief description of the nature of ocean tides.
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Website
NOAA

Noaa: National Data Buoy Center: What Are Tides?

For Students 9th - 10th
A very general introduction to tides and their cycles, with one link to a graph of tide data.