Desmos Activities
Dan Meyer's Blog
Math Open Reference
Quick Tasks
Jo Boaler
Solve Me Mobiles
Same Different
Graphing Stories
Robert Kaplinsky's Blog
Mathematics Vision Project
NCTM's Illuminations
Fraction Maker
Fostering Math Practices
Which One Doesn't Belong
Open Middle
Illustrative Mathematics
Mathematics Assessment Project
Robert Kaplinsky's Problem Based Lesson Search Engine
Beginning of Year Activities
Mathigon