Bracketing is a technique where you take multiple shots of the same scene. One shot will be with a normal exposure, one shot will be over exposed, and another shot will be under exposed. We've discussed how our camera can make mistakes. Bracketing your shots, especially in tricky lighting situations, gives you an insurance policy. Also, during the editing process we can combine these images together into HDR photos or blended exposures.
Bracketing Info - Here is a detailed article about bracketing
AEB - Information about Auto Exposure Bracketing (AEB)
Gimp/Photoshop Elements - Info on blending exposures
The Assignment
Take out an insurance policy on your photos with this rubric.