Yes. Four of them planned for release so far— Olaf and Sven on Thin Ice, Phantoms of Arendelle, All Hail Queen Elsa and Memory and Magic. The first two will come out on September 23th (although the first one will only be available for Kindle) and the other two will come out on January 6th 2015 and later in the year we’ll have other two books.
Olaf and Sven on Thin Ice is manly focus on Olaf and it starts with Olaf eavesdropping on Kristoff and Anna and he thinks that Kristoff is not going to go to work so Olaf “takes on his responsibility” and he and Sven leave although Kristoff follows after them and the chaos they’ve caused.
Phantoms of Arendelle is focused on Anna and Elsa. There’s a party going on for Elsa and as a distraction they run into a secret door that leads to a passage. After they walk in the passage the doors lock behind them so they’re trapped and then spooky things start to happen…
All Hail Queen Elsa is also focused on Anna and Elsa. Anna wants to take Elsa to a pastry shop that makes “the most delicious dessert in all Arendelle”. In their way they come across villagers who all seem to be intimidated by the Queen but Anna shows them that she’s really nice and Anna shows Elsa how to be less “Snow Queen” and have some fun.
And as for Memory and Magic, is yet another book set with Anna and Elsa. This time, Anna and Elsa are growing closer and they’re learning more about each other. Yet, Anna wishes she could remember all the times they played when they were younger with Elsa’s magic.