In college psychology, many years ago, it was said a person cannot motivate another: one can only introduce a stimulus into the environment for the subject to be motivated by his/her own value system. Motivation therefore is an internal process. I have found this to be true. While we all may have shared motivational triggers as others we respond to ours and ours alone. If I have little use or care little for external recognition then introducing it into the learning or work environment will have little or no affect on my efforts. However if I crave recognition by others offering the opportunity to achieve it will affect my efforts greatly. So to "motivate" a student is then to know what the student craves, desires or considers important to him/herself. Then introduce it into the learning environment. Since we all have differing motivational factors multiple stimuli must be presented to a class.