1. A computer readable medium holding computer executable instructions for displaying one or more attributes associated with one of one or more block diagram modeling components of an executable block diagram model, where at least one of the one or more attributes has one or more attribute values, the medium comprising: instructions for displaying an executable block diagram model in a first window, the executable block diagram model comprising a first block diagram modeling component having a first attribute; instructions for associating the first block diagram modeling component with a first graphical affordance; instructions for displaying the first block diagram modeling component with the first graphical affordance; instructions for activating the first graphical affordance in response to a cursor being proximate to the graphical affordance; and instructions for displaying a first widget in response to activating the first graphical affordance, the first widget for displaying a history of attribute values associated with the first block diagram modeling component.