Sven Frank’s course is the #1 search result for the keyword. He offers a 300+ page PDF companion to his video series. Unlike static grammar books, his PDF contains QR codes linking to video explanations.
A 2.0 PDF uses decision trees. Are you talking about a person or a thing? Is the verb dative? Follow the tree. Deutsche Grammatik 2.0 Pdf
Most versions of these materials are licensed under Creative Commons, meaning they can often be used and shared for educational purposes. You can find historical versions, such as Jacob Grimm’s Deutsche Grammatik , on the Internet Archive for linguistic research. Deutsche Grammatik / 2 : Grimm, Jacob - Internet Archive Sven Frank’s course is the #1 search result