Redd construction and counting
Here are four videos (in addition to the two above) that explain or illustrate redd construction and identification. 
Here's a six-minute video assembled by Tiffany Tucker, who teaches 1st grade at the Elm Hill School in Springfield, Vermont. Enjoy!
Artifishal documentary
Yvon Chouniard, founder of the Patagonia company, is an avid outdoorsman and enthusiastic fisher-person. Now he's thrown his financial resources and name behind a project to raise awareness about the dangers posed by aquaculture and hatchery-based stocking programs.

Check it out! It may change the way you think.
Other interesting videos that you and your students might enjoy
Macroinvertebrates
Here are several videos that provide information on macroinvertebrates, their collection, classification, and sensitivity to pollution

Dissection videos
Here are two videos that demonstrate the process of dissecting a trout.