I became fascinated with quantum after reading Feynman's QED. Interested in learning more, the internet pointed me to Mike & Ike's textbook on quantum computing, which I highly recommend. But I find that personally the unstructured and untested nature of it makes it hard to self learn without a large amount of discipline. So I put together a free to use website for anyone else who might be in a similar spot: https://ketsandgates.com/ It has lessons spanning early ideas in quantum computing with refresher material on an as needed basis. It also will actively test your understanding as you go. I was using it offline but assumed there might be others who would benefit from a similar structure so posted it for free.