I've got a book called Mein Erstes Buch ("My First Book"—apologies if I screwed up the spelling, I don't have it with me at the moment to check) that starts at

I've got a book called Mein Erstes Buch ("My First Book"—apologies if I screwed up the spelling, I don't have it with me at the moment to check) that starts at "see spot run" difficulty ("Ball. Red ball. Red ball and Tom. Tom bounces the red ball."—stuff like that) and, through pictures and words, by the end, has you reading at maybe a 4th grade level (whole pages of text, only occasional images). I haven't gone through the whole thing, but I did maybe the first third of it one day, some years back, and it did work—the farther I got, the slower-going it was, but I was learning enough to keep progressing, and the way it was designed, the older parts kept getting reinforced in a kind of spaced-repetition sort of way, so at least temporarily I did have all the earlier material in my head, 100%. Very little of it stuck long term—but then again, I probably didn't spend more than ninety minutes with the book. Not enough on its own to meaningfully learn to read German, but I bet it (or something similar) could be great as part of a larger program incorporating other resources. I was really surprised at how effective it was.