Students have been raising money for the Leukemia and Lymphoma Society.
Teachers agreed that one person would spend a night on the school's roof for each $500 raised.
Nazareth High School Principal Alan Davis said a student who has been fighting the disease was the real inspiration for the plan.
"Thinking about what Karina went through, all of the treatments and fighting that illness, we all kind of thought hey, to spend 12 hours on a roof, in the cold, if she can do what she did and come back with a smile on her face every day, we can certainly do this," Davis told WFMZ-TV.
Ten teachers, including the principal, plan to stay up on the roof until 8 a.m. Thursday.
🔵🦅we still out here .... 🥶‼️ pic.twitter.com/pXiYxoF58U— Alan Davis (@NazHSPrincipal) February 20, 2020