Climate Cardinals invites high school and undergraduate students globally to share a defining moment or insight that shaped how they think about climate action. Entrants can submit in creative writing, analytical writing, speech, or art, and compete for a US$500 grand prize, publication, and recognition. All participants will also gain membership in the ChallengeUS Future Leaders Network, a global community of youth changemakers.

In October 2025, a significant wave of youth-led climate strikes swept across the globe, signalling a resurgence in environmental activism among Generation Z. Organised by movements such as Fridays for Future and Climate Cardinals, a collective demand for urgent action on climate change and environmental justice drove these strikes.