I often turn to children’s books when I need something light and fun, not because children’s books don’t deal with heavy subjects, but because they often do so lightly.
Tuesdays at the Castle, by Jessica Day George is definitely light and fun. The sequel, Wednesdays in the Tower, is out today. (I’m excited to get my hands on it.)
Something by Diana Wynne Jones is always a good choice, though not all of her books are equally light. House of Many Ways would be a good choice. Something by Eva Ibbotson, such as Island of the Aunts or The Secret of Platform 13, would also be a good choice, though again, not all of her books suit. Jones and Ibbotson are experts at creating light and fun magical worlds.
Mrs Piggle-Wiggle, by Betty MacDonald, is a good choice for fun of the ridiculous sort. I haven’t read these books in ages, but was thinking of them recently.
Pippi Longstocking, by Astrid Lindgren, is also good fun of the ridiculous sort.
There are, however, also adult books that I can turn to for light reading.
Any of the Five Hundred Kingdoms books by Mercedes Lackey are a good choice for light and fun reading.
Coronets and Steel by Sherwood Smith is heavy in the politics, but overall very fun and entertaining.
Midnight in Austenland by Shannon Hale might count, but I don’t normally read romances, mysteries, or Jane Austin books, so I don’t know if I can judge. I picked up the Austenland books for light reading, however.
I don’t know where the young adult books are on this list. Surely there are light and fun young adult books, but none come to mind right now.
The closest I can come is Sorcery and Cecelia, by Patricia Wrede and Caroline Stevermer, which is, perhaps, a bit frivolous.
James Herriot’s Cat Stories is a great choice for light reading, but doesn’t really fit age-based categorization. (I started reading James Herriot when I was in 4th grade…)