In this article we present the results of two listening assessments conducted in spring 2013 and fall 2013. Our primary goal is of a pedagogical nature and is concerned with the design and the testing of a tool that could measure students' critical listening skill improvement during the span of a semester. A total of N = 370 students participated in two quasi-experimental studies in which we developed a program to foster and measure critical listening skills. Results show that students' listening skills improved in specific aspects of critical listening at both times. Effects were larger in the second round due to adjustments to both the course curriculum and the assessment tool. Results support the impact of the intervention by modest to high effect sizes and the construct validity of the assessment tool. We consider the improvement that was found in the current study an important beginning and recommend that the practice of listening skills becomes an integral part of the curriculum at the undergraduate level.