I would recommend this series primarily to elementary school students and older students struggling with reading comprehension; however, the Moomin books are written so that they can be enjoyed by people of all ages. I know of adults living in Scandinavia and in Finland who often revisit the beloved stories they enjoyed as children. I myself didn't discover the Moomins until my junior year of high school, but I found them rewarding nevertheless.
The Moomins series can teach American children a lot about Nordic culture and also serve as a gentle reminder to respect all of Earth's living creatures, from plants to animals to the waters and forests they call home. The prose is also quite beautiful, and often evokes vivid mental images of glowing sunsets and magical nights. For a better idea of what I'm talking about, see the quotes I've included below.
“Now dusk fell again. It spread very slowly and carefully, to give the day ample time to go to bed. Small clouds were strewn all over the western sky like dabs of pink whipped cream. They were reflected on the ocean, which rested calm and smooth and looked quite harmless.” - Moominpappa’s Memoirs
“The sun had set, but now in June there was of course no darkness to
speak of. The night was pale and dreamy and full of magic.” - Moominsummer
Madness.
“The sand was raked into smooth little ripples under the clear, green
water, and the rocks were warm in the sunshine. The wind had gone home to
sleep, and there was no horizon to be seen, only a great transparency of
light.” - Moominpappa’s Memoirs
“One evening the western sky was
on fire with the most beautiful sunset she had ever seen. It was a tumult of
red, orange, pink, and yellow flames, filling the clouds above the dark and
stormy sea with smoldering colors. The wind was blowing from the south-west
towards the island from the sharp, coal-black line of the horizon.
As she gazed at the sky, the evening
light crept up the wall, lighting up the flowers in her garden. They seemed to
be alive and shining. The garden opened out, and the gravel path with its
curious perspective suddenly seemed quite right and to lead straight to the
verandah. Moominmamma put her paws round the truck of the tree; it was warm
with sunshine and she felt that the lilac was in bloom.” - Moominpappa at Sea.
