The money will go to feed thousands of school children in Kenya, the charity said.
"I have seen with my own eyes what a difference a simple cup of nutritious porridge can make in a child's life," Barrymore said. "It helps them learn, stay healthy and sets them on track for a bright future. I urge everyone -- everywhere -- to help WFP 'Fill the Cup' for hungry children, and make hunger history."
"We have a dream ... to feed another 10 million hungry school children in Africa by Thanksgiving Day," WFP Executive Director Josette Sheeran said. "Just $50 fills a child's cup for a year, and we call on everyone to click on wfp.org and make a donation."