I like my Answer Keys kept by subject in individual folders. It works so much better than filing them in with my other masters in my huge binder OR in the filing cabinet with the student copies.
When it's time to grade a quiz or test, all I have to do is grab the correct folder! I can also throw it in my teacher bag easily and take it home for grading.
I use a 2 pocket, 3 prong PLASTIC folder for each subject. They will pretty much last FOREVER, unlike their cheaper paper counterparts.
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