I stumbled upon these books that use manga to teach a wide range of subjects. I wish I had such books at my disposal in high school. It would have made my learn experience much more enjoyable. Learning through a medium one has interests in would surely cause a lot less rage quitting than the mundane ritual we all go through in school. While these originate from Japan some have been officially translated and published in English. I have even heard of high schools cataloguing these books in their libraries.
Here’s a google translated link of Amazon Japan’s search results with some surprisingly advanced topics such as:
Now I’m not saying these are great replacements for textbooks. Provided all the information in them are factual, I think books like these will offer excellent introduction or supplemental material for their respective subjects. Unconventional? Maybe. Useful? I think so.