Writers read. Therefore, in preparation for your project, read and study books that have already been published for the adolescent reader. It is necessary to read for research purposes, as well as to gain general knowledge and learn lessons about how professional writers deal with their material. Such reading and research will help you to understand how to handle the vocabulary, subject matter, sentence structure, and length of your story.
Editors and publishers divide children into groups according to age. They define adolescent readers as being between the ages of 10 and 14. The age of your main character will determine the age of your readers. Children prefer to read about someone who is their own age or slightly older. When embarking upon a writing project for a particular age group, it is important to consider a child who is at the upper limit of the age range reading your manuscript. Will someone this age be interested in your story? Will they be able to identify with the main character? Is the situation you have created one that they could imagine being in themselves?
As you develop your main character, keep in mind that they should be complicated and multi-dimensional. Explore their personality and relationships. Throughout the book, the main character should experience some type of growth as they move toward maturity. This is often the heart of a children's novel. As the main character grows and changes, and if the growth feels real, young readers will learn and believe that they, too, will change and grow.
Adolescents don't like to think of themselves as kids, so stories written for them should move beyond home and school. Their reading material should reflect a larger community that includes their peers. Adolescents crave intense situations; therefore, stories written for them should address adult problems, growing pains, tough choices and finding solutions. The characters in stories for adolescents should confront dramatic situations while proving their adulthood.
Editors and publishers specify length requirements for different age groups. For adolescent readers, sentences should be approximately 20 words, and paragraphs up to 10 sentences. Book lengths for adolescents should be approximately 35,000 words.