Supplemental instruction (SI) is group study that is tailored towards open discussion and crowd-sourcing.  SI sessions are held by students (SI leaders) who themselves have done well in the class and have been trained in appropriate application of study strategies.  Students who attend have the opportunity to become actively involved in the course material as the SI leader uses the text, lecture notes, and other materials helpful in understanding the course.  Attendance is open to all students independent of class performance.  SI sessions are completely voluntary and 100% confidential and students who do attend SI sessions have historically done better in courses than students who do not.  It is efficient, effective, and free!