The tenth of the new series of contests, and the first annual Math Day, was held on Thursday, October 8, 2015 in the Student Union on the Stillwater campus of OSU. Approximately 275 students participated from the following schools in Oklahoma, Texas, Kansas, and Alabama: Adair, Blair, Bray-Doyle, Colcord, Deer Creek Lamont, Dove Science, Elk City, Graham-Dustin, Haskell, Hinton, Hirschi, Keys, Maize, Meeker, Morris, Moss, Oakridge, OSSM-Oklahoma City, OSSM-Tahlequah/Stilwell, Porter Consolidated, Quapaw, Santa Fe, Seminole, Snyder, Springer, St. Mark's, Union, and Vestavia Hills.
The Math Day is held annually in the fall. The day is in two parts. The first part is an individual contest consisting of approximately 25 multiple choice questions. The second part consists of breakout sessions including public talks by OSU faculty, a low-intensity team round, and activities run by the OSU math club.
Next year's contest will tentatively be held in early October.