My Very Exciting Magic Carpet Just Sailed Under Nine Palace Elephants.
That sentence will help you remember the names of the planets in order from the Sun. Did you know we're up to 11 planets in our solar system? Three of those are dwarf planets but have been able to retain their place in our system and each have their own word in the sentence above. High honor, indeed.
I highly recommend this book, published by National Geographic, in 2008. That's pretty recent, but hurry and read it now anyway, because you never know when something is going to change in astronomy. According to Aguilar, "Almost every week another planet is discovered orbiting a distant star."
11 Planets layout is very kid-reader friendly. Big pictures of each planet accompany 1-2 paragraphs of information. Interesting graphics and facts are off to the side of the main text. Artwork showing the god or goddess the planet is named after and the planet's symbol are part of each page. (I didn't know each planet had it's own symbol, did you?) Some of the pictures are actual photographs taken by amazing machines which are out in space right now, sending back fascinating images. Take a peek at Victoria crater which lies on Mars near its equator. This photo was taken by the HIRSE orbiter. Find it on page 23.
11 Planets is a great book for boys or girls and would have particular appeal to reluctant readers. Look for it in Nonfiction, in the 500's.