OSL Calendar of Events 2009-10
| Date | Event | More Information |
| Aug 30-Sept 3 | PennCORP, PennQuest, PENNacle, PENNarts, PENNgreen | Civic House, Student Life, Platt House |
| Sept 3 | NSO begins | CHAS |
| Sept 8 | Student Organization Fair | Student Life, SAC, NSO |
| Sept 8 | Convocation | President's Office |
| Sept 9 | First day of classes | |
| Sept 19-20 | Rosh Hashanah (begins at sundown on Sept 18) | |
| Sept 25 | Tom De Luca, hypnotist | Sophomore Class Board |
| Sept 27 | Yom Kippur (begins at sundown on Sept 26) | |
| Oct 2-4 | Fall Leadership Weekend | Student Life |
| Oct 17 | Diwali | |
| Oct 17-19 | Fall Break | |
| Oct 23-25 | Family Weekend | Student Life |
| Oct 30 | FrightFest | SPEC, Student Life |
| Nov 7 | Homecoming | Alumni Relations, Student Life |
| Nov 26-29 | Thanksgiving break | |
| Dec 4 | WinterFest | SPEC, Student Life |
| Dec 10 | Last day of classes | |
| Dec 11-14 | Reading days | |
| Dec 15-22 | Final exams | |
| Dec 22-Jan 12 | Winter break | |
| Jan 13 | First day of classes | |
| Jan 17 | Spring Activities Fair | SAC, Student Life |
| Jan 18 | MLK Day | |
| Jan 29-31 | Spring Leadership Retreat | Student Life |
| Feb 12 | LoveFest | SPEC, Student Life |
| Mar 6-14 | Spring break | |
| Mar 30-Apr 5 | Passover begins at sundown on Mar 29 | |
| April 2 | Good Friday | |
| April 4 | Easter Sunday | |
| Apr 16-17 | Spring Fling | SPEC, Student Life |
| Apr 22-24 | Penn Relays | Athletics |
| Apr 23 | Hey Day | Student Life, Class of 2011 |
| Apr 27 | Last day of classes | |
| Apr 28-30 | Reading days | |
| May 3-11 | Final exams | |
| May 11-15 | Senior Week | Student Life, Class of 2010 |
| May 15 | Ivy Day | Student Life |
| May 15 | Alumni Day | Alumni Relations |
| May 16 | Baccalaureate | Chaplain's Office |
| May 17 | Commencement | |