Uxcel - The easiest way to learn UX/UI design
Weekly UX Exercise - Receive challenges top companies use to interview designers
Daily UI - Become a better designer in 100 days
UXCurate - Practice whiteboard challenges and get feedback 👨🎨🎨
GoodBrief - A random generator for design briefs.
A Product Design Challenge - Get a design challenge to solve real-world problems