Holding handmade posters and sunflowers, Oak Knoll School students and their parents walked the Menlo Park school's track on three days this week to send a message of hope to Ukrainian children and refugees worldwide.

The peace walks, organized by students and staff, took place on Monday, Tuesday and Wednesday mornings, March 21-23, to show support for children fleeing Ukraine after Russia invaded the country last month.

Some 4.3 million children, over half of Ukraine's child population, have been displaced by the war, according to UNICEF. More than 1.8 million children have crossed into neighboring countries as refugees and 2.5 million have been internally displaced inside the country, UNICEF reported on Thursday, March 24.

"Finding a way for students to share their thinking and raise awareness that is appropriate for our students, who are between 3 years old at our Early Learning Center (preschool on campus) and our fifth graders, led us to the idea of a Peace Walk," said Principal Alicia Payton-Miyazaki in an email. "We have staff and families from Ukraine and Russia who are deeply committed to returning to peace and supporting the communities who have been affected by this war."

School administrators invited families to donate to the Red Cross and UNICEF to help provide humanitarian relief.