degrimm1-8, Exercise 3: Dictionary or tales?

Model answer (one possible balanced paragraph):

For the tales: they reached a huge general readership across the world, were translated into very many languages and gave the brothers a lasting public name, which no scholarly work has matched.

For the dictionary and the other scholarship: these shaped academic fields (historical linguistics, Germanic philology, folklore) and the dictionary remains a reference for the history of German words. The brothers themselves seem to have valued the scholarly work highly (check their own statements).

A fair conclusion: they matter in different ways. The tales are more important for culture and readers, and the scholarship for the academic study of language. The tales, in addition, are part of the scholarship, since the brothers meant them as a work of folk-culture research (Chapters 2 and 4). Which one is "more important" depends on the criterion, and saying so is a better answer than choosing one without reasons.