Student involvement in their own assessment can add reflection and metacognition to the learning process. Based on this idea, an assessment instrument was developed to self-assess college students' mathematical problem solving tasks. The main objective of this exercise is to improve student learning. The assessment instrument contains three items: student opinion questionnaire, an analytic evaluation rubric, and a self assessment schedule. A peer assessment component was also included in the assessment process to gain more accuracy. The rubric will serve three main purposes. First, students can use the rubric as a learning tool. Second, it will serve as a teaching tool for teachers. Third, it can be used as an assessment tool. However, the whole purpose is to improve student learning rather than providing them with a letter grade.