On October 3, 2015, at its home football game against Arizona, for the second consecutive year Stanford competed in the national Game Day Challenge organized by the U.S. Environmental Protection Agency. Each participating school selects one home football game at which to heavily promote zero-waste initiatives and measures and reports the amounts of recycling, compost, and landfill waste resulting from the game. This year, Stanford focused on amplifying fan engagement by adding eight unique measures to increase sustainability awareness, such as sending emails before the game, placing signage with sustainability factoids around the stadium, showing a video about Sustainable Stanford during halftime, and greening one of the staff tailgates.

In February, Stanford further expanded its game day sustainability efforts in conjunction with the national RecycleMania competition and the Pac-12 Zero Waste Challenge. Stanford selected two basketball games at which to promote sustainability by not only using fan engagement tactics, but also adding compost bins throughout Maples Pavilion. The addition of compost bins increased the diversion rate for the selected men’s basketball game from 6.55% to 28.57% and spurred a deeper interest in adding permanent composting infrastructure both inside and outside Athletics venues.