Read several tween fantasy novels cover to cover. While reading, highlight or underline any passages you find particularly moving.
Create a list of your favorite and least favorite things about each novel. For example, "compelling fantasy world" and "detailed descriptions" might be on your favorite things list, and "lack of character development" and "dull love interest" could be on your least favorite things list. Refer to this list as your plan and write to focus on emphasizing the strengths of the genre and minimizing common writing problems.
Write a one- to two-sentence summary of your fantasy book. The summary includes a brief character description and plot synopsis. For example, a summary for Stephenie Meyer's "Twilight" series may read: "A troubled young women falls in love with a vampire, placing her life in danger."
Read your summary and asses its viability as a tween fantasy novel. Does the summary contain information that interests tweens such as duels, adventure and friendship? Are mythological elements present? If possible, add references to popular mythological creates such as fairies, witches, wizards, dragons and elves. Add references to other elements of mythology, such as spells and magic.
Expand your one-sentence summary to a several paragraph summary. Include a biography that explains the protagonist's age and history, and why she begins an adventure. Include several plot points that relate to fantasy elements. For example, C. S. Lewis's classic fantasy novel, "The Lion, the Witch and the Wardrobe," contains a plot point where the protagonist discovers a magical portal.
Write a one-sentence biography for every major character. For example, write "The villain is an evil witch who wants to take over the kingdom." Look over the biography and replace ordinary powers, skills or attributes with fantasy-based attributes, if possible. For example, turn a character's running skills into the ability to fly on a broomstick.
Read over your summary and determine if it contains adequate conflict. In classic storytelling, the protagonist wants something and faces a series of obstacles. Are the obstacles your protagonist faces true challenges or minor hurdles? Do the fantasy elements of the story elevate the conflict? In a three-act story, the protagonist faces at least three major obstacles.
Expand your several-paragraph summary into a detailed plot and character synopsis. Write a brief overview of the initial setup, including the location and mythology of the world of your story. For each plot point, write several paragraphs that cover the specific actions the protagonist faces and the reactions she experiences. Explain the fantasy elements that make the protagonist's obstacles different than the obstacles she would face in the real world.
Write the novel using your synopsis as a guide.