There are almost as many variations on a 3-1-3 schedule as there are students enrolled. However, those students seriously interested in saving a year of study would typically take calculus or math 12 and physics at their high school. These courses, when successfully completed, would earn 6 credit hours each of college credit and be entered on the college transcript as SD math or science and the grade on the college transcript would be satisfactory/unsatisfactory (pass/fail). This student would also be enrolled in three courses at the college including one English course and one social science course (American Government or Economics) each semester. The student may also choose a third college course each semester for a total of 9 credit hours per semester. So, by June, when the high school courses had been completed and grades sent to the college registrar, the student would have earned and have entered on his/her college transcript, 30 credit hours, which is a full year of college credit.
Some high schools schedule math 12 and physics in the morning and some in the afternoon. Either way, students are able to schedule their college classes, which usually meet on a Monday/Wednesday/Friday schedule, for the other half of the day.