I appreciate this book as a classic work for younger readers; this has the hallmarks of timeless fiction meant for such an audience - namely, it's a quick read with a quick plot (for instance, REVEL in how instantaneous Calvin's obvious love for Meg is!) and a HELL of a quick ending that almost left me reeling amidst what felt much like a saccharine whirlwind and then DONE.
Things I noticed this go-around, all that being said: what an interplay between faith and science, and thinking and feeling that happens in this work, and how obvious these two themes are as they work together to propel the plot and the children onward. On one hand, we have inter-dimensional travel, aliens and talk of higher and lower dimensions; on the other, very obviously Christian-themed quotes are sprinkled in particularly as our vulnerable human Meg struggles with her own furious immaturity and the fact that She Has To Go Do the Things (aka grow up.)
So there's that, and again with the pair of hands, one being Camatzotz and its rigidity of thought/being, and then there's that planet Aunt Beast dwells on, where the creatures can't see but sense, and care. It all seems so obvious looking at it, now. But it wouldn't necessarily be, for younger folks who learn by witnessing those like them be strong where they need to be in a tough, confusing world. And I appreciate that all the more these days. I just happen to have more patience than certain plot points provide for, and that's okay.
TLDR: It's a typical teen novel that's written very concisely, and well. Within it are all sorts of things going on that my now-adult brain latches onto, and finds enriching, particularly knowing how long ago this book was written. I think that speaks, ultimately, to the timelessness of A Wrinkle in Time.