This year's theme was "Dancing Through The Decades," and each Greek Life group was assigned a decade from the 1920s all the way to today's hits.
Panhellenic Council will hold its annual "Greek Sing" lip-sync competition to raise money for the Gayle Beyer's Scholarship and various philanthropies.
The Piazza Center is focused on preventing activities like hazing and substance abuse in order to create a safer Greek Life experience.
There will be games, music, food, and of course, trick-or-treating.
"We are grateful and fully supportive of Lionsgate and Hulu taking on this project related to our son's tragic and very preventable death," Jim and Evelyn Piazza told the Hollywood Reporter.
Penn State's Panhellenic Council will host multiple events over the week as a trial for the Circle of Sisterhood foundation.