These two pictures, high-key and low-key. The image showing the dark corners and a bright window is best describe as a low-key because of the darkness surrounding the window and its the main focal point. As for the image of the book bag, it shows the High-key since there are barely dark areas showing and its mostly light.
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Those are great examples of high and low key images. I like how you chose the dark classroom and how everywhere is dark besides the brightness of the windows. Although there are some bright reflection on the floor it is still a good example of a low key photograph. The picture of the book bag shows a great example of low key since the picture seems to be taken in a well lit area. The book bag is the main focus and it is the only dark park of the photo while everything else is bright. However, you could have chosen a better subject for the low key image since the book bag is predominantly dark and focuses away from the brightness of the photograph. You could have taken it farther back and the low key photograph would of been even better.