(237e) Mastery Learning in the Mass Balances Class

The first year of the chemical engineering curriculum is critical to student success. The principles of mass and energy balances (MEB) taught then are the basis for problem solving in virtually all subsequent classes.

The desire to have students demonstrate a minimum level of mastery has led to the introduction of mastery learning in MEB. Mastery learning is based on the premise that all students can achieve a desired level of understanding if given sufficient time and resources. Resources include classroom instruction material as well as individual and group tutoring with mentors, graduate teaching assistants, and instructors.

For MEB, the mass balances content was divided into individual learning concepts, e.g., unit conversion and solving mass balances for a recycle problem with reaction. A series of problems were developed for each concept and deployed as quizzes in the Blackboard course management system. Random values are assigned to specific variables so a single correct answer does not exist.

Students must obtain the correct answer to receive credit for a quiz. No partial credit is given. Since the quizzes constitute 72% of the grade, successful completion of the quizzes is required to obtain a passing grade. If a student does not pass a quiz on their first attempt, they may retake it an unlimited number of times. Between attempts, students are encouraged to seek help through a review of instructional material or help from others.

Student responses have been favorable. They appreciate having unlimited time to work problems. They also appreciate the opportunity to review concepts and correct errors if they do not obtain the correct answer.

Blackboard provides summary data on the number of attempts and time per attempt for each quiz. This information has been used to develop two metrics of student learning that the instructor can use to improve student performance:

1. Conceptual Understanding
2. Solution Effort

Differences in the percentage of students who complete the quiz on their first attempt (as opposed to multiple attempts) indicate how well students understand the concepts. If most students complete the quiz on their first attempt, current instructional approaches are effective in preparing students. Otherwise, modifications may be beneficial.

Differences in the time required to obtain the correct solution indicate the effort required to solve the problem. The total reflects both the time required to transform the problem statement into a mathematical expression and the time to solve the equations. Providing an anticipated solution time for students may help students prepare mentally and allot sufficient time to complete the quiz thereby fostering self-motivation.

Results for both metrics are presented and use of the data to improve instruction discussed.