I greatly enjoyed Lewis Carrolls humor and his many uses of puns and homonyms (words that sound alike but have different meanings). It was a very easy read for me and rather enjoyable. However, I do not think a younger child would understand a lot of what is going on, especially if it is being read aloud to them. For example: I started reading this book out loud to a couple of kids, and usually when I read a book and stop at the end of a chapter they beg for me to continue, but with this book, when we came to a stopping place they vanished from the room without a word about continuing. Carroll does tend to write part of a sentence and then add, in ( )'s some explanation and then continue his sentence, which can be quite confusing for a younger child, especially if they are not the one reading it. For example:
Down, down, down. Would the fall never come to an end! `I wonder how many miles I've fallen by this time?' she said aloud. `I must be getting somewhere near the centre of the earth. Let me see: that would be four thousand miles down, I think--' (for, you see, Alice had learnt several things of this sort in her lessons in the schoolroom, and though this was not a very good opportunity for showing off her knowledge, as there was no one to listen to her, still it was good practice to say it over) `--yes, that's about the right distance--but then I wonder what Latitude or Longitude I've got to?' (Alice had no idea what Latitude was, or Longitude either, but thought they were nice grand words to say.)
Presently she began again. `I wonder if I shall fall right through the earth! How funny it'll seem to come out among the people that walk with their heads downward! The Antipathies, I think--' (she was rather glad there was no one listening, this time, as it didn't sound at all the right word) `--but I shall have to ask them what the name of the country is, you know. Please, Ma'am, is this New Zealand or Australia?' (and she tried to curtsey as she spoke--fancy curtseying as you're falling through the air! Do you think you could manage it?) `And what an ignorant little girl she'll think me for asking! No, it'll never do to ask: perhaps I shall see it written up somewhere.'
Carroll also has an older style of writing and spelling, which may be slightly confusing to some.
So, all that to say, I liked the book, but I don't know that I would label it as a children's book so much as a young adult's book.