Crash Course is a YouTube channel that has some great educational videos. They have six Biology videos that can be used with high school classes.
Topics include: Plant Cells, Membranes and Transport, Animal Cells, Biological Molecules, Water, and Carbon. They are fast paced and well produced.
As with any resource, make sure you view the videos before showing them in class to make sure they are appropriate for you school and for the topic you are studying.
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