I recall two enjoyable books, both by Morton Rhue, being boot camp and the wave (and one that I liked but most people didn't, kafka's metamorphosis. Sure didn't like having to interpret that though).

At least early on they tried making us read enjoyable books, as in modern books aimed at teenagers, they just... weren't very good.

I think the peak of unenjoyment for me was Das Parfüm, which is technically somewhat modern. I tried reading it and was so bored I just couldn't continue, ended up reading a synopsis somewhere and pretended to know what i was talking about.

At least it never killed reading for me because by the time school made me read books I was already reading fantasy novels in my free time anyway.