As part of the conference on plastics and sustainability held by the City of Cupertino's Mayor Darcy Paul, winning projects from the 2021 S⁴ competition were presented to an audience. These projects, which focused on improving our environment and reducing plastic waste, included Ashmit Kachhawa's Plastic Imagination, a 3-D printer filament maker that reuses plastics for 3-D printing, Matthew Leung's All-In-One, an AI-enabled trash can that automatically sorts recycling, Mugdha Shinde and Namya Bhargava's PlastiNo, a reverse recycling vending machine for easy recycling, and Kalya Pradeep's idea of breaking down plastic using CMC.