<p>The quarter system is not particularly unique to Dartmouth. What is more unusual there is the D-plan, which encourages students to attend during the summer (normally the lightest enrollment) while not guaranteeing four fall quarters (normally the heaviest enrollment).</p>
<p>The quarter system does have some additional overhead. While three quarters and two semesters have the same 30 weeks of instruction, the quarter system will have one extra set of overhead days (a few days before classes start for last day registration matters, a week or two of final exams after classes end) per year. That is in addition to doing the scheduling and registration work one additional time per year.</p>
<p>At semester system schools, the summer term is typically a half length term, so a student taking a full time course load in the summer would take about half as many courses or credits at double the speed.</p>