Tinker Day, observed since the 1880s, occurs in October. It became an official holiday in 1895. The surprise element, which was introduced in 1899, adds to the excitement of the day. After the president's official declaration, classes are canceled and students, faculty, and staff hike Tinker Mountain attired in zany costumes for songs and a traditional picnic of fried chicken and Tinker Cake.
Roanoke Times article, 10/25/12