Overall a good program, but could use some work on the layout. The fine or faint text font is hard to read for hours on end, I would suggest a bold font instead, as well as arranging the information on each page so that it can be viewed at once, rather than having to scroll down the page unnecessarily. In several places the information could be fleshed out more, as an example the idea of going upstream or downstream and how this applies in tidal areas is not clear. Also I found some test questions were asked when the information wasn't presented until the next module.