But Friday's splash is bittersweet because they are the last graduating class of a storied high school that's about to shut its doors.
It's the ceremonial jump and dip to mark their four years at John W. Hallahan Catholic Girls High School.
But this tradition meant so much more Friday and came with so much emotion.
"It's really important to be the last class because the sisterhood is so overwhelming, and all the alum came in with us," said graduating senior Sabine Cress.
Graduating senior Sanah Jones said, "When we all found out that Hallahan was closing, we were sad, but nothing like the emotions that we're feeling now. Today, it's so real and just overwhelming, but at the same time, it's joyful."
After 110 years, Hallahan is closing its doors at the end of this school year due to financial trouble and low enrollment.
The event was filled with memories and tears, and alumni joined this last official class.
"There are just so many memories and heartbreak for the school and sadness," said Gail Ward, Class of 1997. "My daughter will never know or experience this sisterhood. This brings back memories of my time here, and we are sad to know it's coming to an end."
The Friends of Hallahan are determined to continue with the founder's legacy.
They're now working to build a brand new school.