Have you taken a look at the Haskell Programming from first principles book? They have a lot of exercises with each chapter.
It's an absolutely fantastic book... but you're asking someone to swallow that first chapter on Lambda Calculus. Maybe that's the best approach, but I can see it completely scaring off an entire class (or classes) of programmers.
On the surface, LYAH looks a lot more polished. It has nice drawings, less typos, seems like an actual book rather than a gathering of notes and thoughts turned into teaching material. But the exercises in LCTHW are amazing. They always challenge my knowledge in a way that often makes me realize that I didn't understand anything from the prior paragraph.
In LYAH I usually tried following along in GHCI to get an intuitive idea of the functions and patterns used. Yet, whenever I sit down to just build something that, while using the same features, deviates from the example code quite a lot, I often notice glaring holes in my understanding of the topics.
And so, bottom line, I want teaching material to ask hard questions which challenge my assumptions and perceived understanding. As a beginner, I can't come up with such questions on my own. Just presenting me with already assembled programs and going through them line by line just doesn't work (for me at least).