In my last post, I mentioned that older son loves to read series of books — the longer the better. Before he read the Percy Jackson series, he read all of Mary Pope Osborne’s Magic Tree House books. He’ll still read the latest one for old times’ sake: he read the latest, Magic Tree House #43: Leprechaun in Late Winter and pronounced it “very good.” His little brother the kindergartener loves them too, so we read them aloud to him on the bus to and from school.

Appropriately enough given this week’s snowy weather on the East Coast, we’ve been reading book #36 in the series, Blizzard of the Blue Moon, which is set in New York in 1938 during the Great Depression. For those of you who don’t know the series, the premise is that eight-year-old Jack and seven-year-old Annie, two kids who live in “Frog Creek, Pennsylvania,” discover a magic tree house in the woods near their house: the tree house is full of books and when you point to one and say, “I want to go there,” well, you go there, wherever “there” is. Their first four adventures take them to the time of the dinosaurs, to the middle ages, and to ancient Egypt. They learn that the tree house belongs to Morgan le Fay, who is portrayed as the magical librarian of King Arthur’s Camelot. (She’s much friendlier than any other version of Morgan le Fay I’ve ever encountered: remember Helen Mirren‘s characterization in John Boorman’s Excalibur?!)

The books are very formulaic, as Morgan sends them on various missions that last about 10 chapters. The description of the tree house embarking on its journey is always the same, and my son can now recite it by heart. He’s learning about genre, which is fine by me. But in book 29 Christmas in Camelot, Osborne varies her formula: it is Merlin who sends Jack and Annie on their missions, four of them to mythical places like Camelot, and four to real-life places like Paris at the time of the Exposition Universelle (for which the Eiffel Tower was built).

Blizzard of a Blue Moon is one of these Merlin missions, and my son is enjoying hearing about places he knows: like Central Park and the IRT subway, which costs a nickel in 1938. Reading the book made me remember those old cross-shaped wooden turnstiles that were still installed in a few subway stations when I was growing up. Here’s a picture from the New York Transit Museum:

Note the fare: 5 cents! (Click here for more information about this particular photo, which comes from a wonderful collection of photos and images at nycsubway.org. The site is a treasure trove for subway buffs; in addition to the pictures, there is a wonderful collection of map PDFs.)

By the way, Jack and Annie’s mission in 1938 New York involves rescuing a unicorn that has been enchanted. Where do you suppose they end up?

The Cloisters, of course, with its Hunt of the Unicorn tapestries.