Amazon Bracket: a fully managed service that helps you get started with quantum computing by providing a development environment to explore and design quantum algorithms, test them on simulated quantum computers, and run them on your choice of different quantum hardware technologies; try their free tier
Elements of AI: series of free online courses created by Reaktor and the University of Helsinki to teach the basics of artificial intelligence
Google for Education: basic computer science curriculum for kids aged 9-14 (or equivalent skill levels)
Open Source Society University: path to a free self-taught education in Computer Science
Pwn.college: first-stage education platform to teach the basics of cybersecurity (Note: it’s in beta, so there may be malfunctioning parts of the website)
SQL Murder Mystery: murder mystery game that helps practice SQL programming skills