New Composition Guidelines - Reference Request
I have a friend who has created many compositions for college level students, but currently finds himself tasked to create a composition for beginning students (middle school / high school). He is looking for a reference book that will help him develop a composition that is consistent with students at this level, rather than college graduates students. (He wants to make sure the composition is interesting, but not too difficult). This task is for band ensemble, not specifically the saxophone.
Do you know of any books that might help a composer faced with this task?