When I was in elementary school, I read Madeleine L'Engle's A Wrinkle in Time. I loved that book. But the sequel, A Wind in the Door, ruled as my favorite for years and years. My ten-year-old mind was blown by, among other things, the notions of scale and perspective in that book. I've adored science fiction ever since.
This little bit of awesome would have gone along nicely.