The event takes place from noon to 6 p.m. Sunday, at Tracy Park in Portsmouth.
Activities include an auction and music by Mighty Fine. Food will be prepared by LIFE Ambulance.
Brenda Porter, who lives in the Clay School District, said when she learned about Hempill's situation, she wanted to help, so she has been assisting in coordinating the activities.
"He is a young man who graduated from Clay, went to OSU (The Ohio State University), and this is his third bout with leukemia," Porter said. "He's waiting on his second transplant at the M.D. Anderson Cancer Center in Houston, (Texas)."
Hempill, 24, and his family have been in Houston since about Aug. 24, Porter said. His mother is a teacher at Rosemount Elementary.
Porter said teachers have been donating all summer long. She recently conducted a yard sale and raised $1,300, she said.
Because of the generosity of everyone in the Clay School District, Porter said, "it's a wonderful place to live."
She said everything has been donated for Sunday's event, including the band's performance, the food prepared by LIFE Ambulance, items for a silent auction donated by local businesses, Pepsi has donated refreshments and the use of Tracy Park also has been donated.