The Berenstain Bears on the Moon
tells a story of how Brother and Sister Bear went to the moon, and what they saw and did there.
This one is written in verse, rather than prose, and considering the limited story, it's a good thing: "The bears put up a flag, took notes, and collected rocks." wouldn't be nearly as nice to read as "Then they fly their flag./They take moon notes./They collect moon rocks/in their moon rock totes." Not that the poetry is that great, but at least it's a little more interesting this way.
(The full review is posted on my blog