Emotions are an important aspect of human behavior that should be included in cognitive models. Including them in a cognitive architecture is the safest way to ensure consistency, and to get reuse. We demonstrate here how interest, distress, and pleasure, three primary emotions shown by children when problem solving, can be implemented in a specific ACT-R (Anderson & Lebiere, 1998) model. These emotions can be initially implemented by modifying some of the ACT-R problem solving mechanisms and our reusable model of vision. While emotions can be a result of information and knowledge processing, they are not purely cognitive processes. They may result in bodily changes (hormones etc.) that influence behavior, perception and decision making. Our task is to implement a simple theory of emotions into the ACT-R cognitive architecture and test it on an existing model of human behavior.